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REVISION AND PRACTICE
Revision and practice with explained answers
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YOUR COURSE DATA · TRY IT HERE
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BhuvaneshMaths 68 · Erode
- CardNo
- 0
- Name
- Bhuvanesh
- Gender
- M
- DateOfBirth
- 7 Nov
- CityTown
- Erode
- Mathematics
- 68
- Physics
- 64
- Chemistry
- 78
- Total
- 210
HarishMaths 62 · Salem
- CardNo
- 1
- Name
- Harish
- Gender
- M
- DateOfBirth
- 3 Jun
- CityTown
- Salem
- Mathematics
- 62
- Physics
- 45
- Chemistry
- 91
- Total
- 198
ShashankMaths 57 · Chennai
- CardNo
- 2
- Name
- Shashank
- Gender
- M
- DateOfBirth
- 4 Jan
- CityTown
- Chennai
- Mathematics
- 57
- Physics
- 54
- Chemistry
- 77
- Total
- 188
RidaMaths 42 · Chennai
- CardNo
- 3
- Name
- Rida
- Gender
- F
- DateOfBirth
- 5 May
- CityTown
- Chennai
- Mathematics
- 42
- Physics
- 53
- Chemistry
- 78
- Total
- 173
RitikaMaths 87 · Madurai
- CardNo
- 4
- Name
- Ritika
- Gender
- F
- DateOfBirth
- 17 Nov
- CityTown
- Madurai
- Mathematics
- 87
- Physics
- 64
- Chemistry
- 89
- Total
- 240
AkshayaMaths 71 · Chennai
- CardNo
- 5
- Name
- Akshaya
- Gender
- F
- DateOfBirth
- 8 Feb
- CityTown
- Chennai
- Mathematics
- 71
- Physics
- 92
- Chemistry
- 84
- Total
- 247
SameerMaths 81 · Ambur
- CardNo
- 6
- Name
- Sameer
- Gender
- M
- DateOfBirth
- 23 Mar
- CityTown
- Ambur
- Mathematics
- 81
- Physics
- 82
- Chemistry
- 87
- Total
- 250
AdityaMaths 84 · Vellore
- CardNo
- 7
- Name
- Aditya
- Gender
- M
- DateOfBirth
- 15 Mar
- CityTown
- Vellore
- Mathematics
- 84
- Physics
- 92
- Chemistry
- 76
- Total
- 252
SuryaMaths 74 · Bengaluru
- CardNo
- 8
- Name
- Surya
- Gender
- M
- DateOfBirth
- 28 Feb
- CityTown
- Bengaluru
- Mathematics
- 74
- Physics
- 64
- Chemistry
- 51
- Total
- 189
ClarenceMaths 63 · Bengaluru
- CardNo
- 9
- Name
- Clarence
- Gender
- M
- DateOfBirth
- 6 Dec
- CityTown
- Bengaluru
- Mathematics
- 63
- Physics
- 88
- Chemistry
- 73
- Total
- 224
KavyaMaths 64 · Chennai
- CardNo
- 10
- Name
- Kavya
- Gender
- F
- DateOfBirth
- 12 Jan
- CityTown
- Chennai
- Mathematics
- 64
- Physics
- 72
- Chemistry
- 68
- Total
- 204
RahulMaths 97 · Bengaluru
- CardNo
- 11
- Name
- Rahul
- Gender
- M
- DateOfBirth
- 30 Apr
- CityTown
- Bengaluru
- Mathematics
- 97
- Physics
- 92
- Chemistry
- 92
- Total
- 281
SrinidhiMaths 52 · Chennai
- CardNo
- 12
- Name
- Srinidhi
- Gender
- F
- DateOfBirth
- 14 Jan
- CityTown
- Chennai
- Mathematics
- 52
- Physics
- 64
- Chemistry
- 71
- Total
- 187
GopiMaths 65 · Madurai
- CardNo
- 13
- Name
- Gopi
- Gender
- M
- DateOfBirth
- 6 May
- CityTown
- Madurai
- Mathematics
- 65
- Physics
- 73
- Chemistry
- 89
- Total
- 227
SophiaMaths 89 · Trichy
- CardNo
- 14
- Name
- Sophia
- Gender
- F
- DateOfBirth
- 23 July
- CityTown
- Trichy
- Mathematics
- 89
- Physics
- 62
- Chemistry
- 93
- Total
- 244
GoutamiMaths 76 · Theni
- CardNo
- 15
- Name
- Goutami
- Gender
- F
- DateOfBirth
- 22 Sep
- CityTown
- Theni
- Mathematics
- 76
- Physics
- 58
- Chemistry
- 90
- Total
- 224
TauseefMaths 87 · Trichy
- CardNo
- 16
- Name
- Tauseef
- Gender
- M
- DateOfBirth
- 30 Dec
- CityTown
- Trichy
- Mathematics
- 87
- Physics
- 86
- Chemistry
- 43
- Total
- 216
ArshadMaths 62 · Chennai
- CardNo
- 17
- Name
- Arshad
- Gender
- M
- DateOfBirth
- 14 Dec
- CityTown
- Chennai
- Mathematics
- 62
- Physics
- 81
- Chemistry
- 67
- Total
- 210
AbiramiMaths 72 · Erode
- CardNo
- 18
- Name
- Abirami
- Gender
- F
- DateOfBirth
- 9 Oct
- CityTown
- Erode
- Mathematics
- 72
- Physics
- 92
- Chemistry
- 97
- Total
- 261
VetrivelMaths 56 · Trichy
- CardNo
- 19
- Name
- Vetrivel
- Gender
- M
- DateOfBirth
- 30 Aug
- CityTown
- Trichy
- Mathematics
- 56
- Physics
- 78
- Chemistry
- 62
- Total
- 196
KalyanMaths 93 · Vellore
- CardNo
- 20
- Name
- Kalyan
- Gender
- M
- DateOfBirth
- 17 Sep
- CityTown
- Vellore
- Mathematics
- 93
- Physics
- 68
- Chemistry
- 91
- Total
- 252
MonikaMaths 78 · Bengaluru
- CardNo
- 21
- Name
- Monika
- Gender
- F
- DateOfBirth
- 15 Mar
- CityTown
- Bengaluru
- Mathematics
- 78
- Physics
- 69
- Chemistry
- 74
- Total
- 221
PriyaMaths 62 · Nagercoil
- CardNo
- 22
- Name
- Priya
- Gender
- F
- DateOfBirth
- 17 Jul
- CityTown
- Nagercoil
- Mathematics
- 62
- Physics
- 62
- Chemistry
- 57
- Total
- 181
DeepikaMaths 97 · Bengaluru
- CardNo
- 23
- Name
- Deepika
- Gender
- F
- DateOfBirth
- 13 May
- CityTown
- Bengaluru
- Mathematics
- 97
- Physics
- 91
- Chemistry
- 88
- Total
- 276
SiddharthMaths 44 · Madurai
- CardNo
- 24
- Name
- Siddharth
- Gender
- M
- DateOfBirth
- 26 Dec
- CityTown
- Madurai
- Mathematics
- 44
- Physics
- 72
- Chemistry
- 58
- Total
- 174
GeetaMaths 87 · Chennai
- CardNo
- 25
- Name
- Geeta
- Gender
- F
- DateOfBirth
- 16 May
- CityTown
- Chennai
- Mathematics
- 87
- Physics
- 75
- Chemistry
- 92
- Total
- 254
JKMaths 74 · Chennai
- CardNo
- 26
- Name
- JK
- Gender
- M
- DateOfBirth
- 22 Jul
- CityTown
- Chennai
- Mathematics
- 74
- Physics
- 71
- Chemistry
- 82
- Total
- 227
JaganMaths 81 · Madurai
- CardNo
- 27
- Name
- Jagan
- Gender
- M
- DateOfBirth
- 4 Mar
- CityTown
- Madurai
- Mathematics
- 81
- Physics
- 76
- Chemistry
- 52
- Total
- 209
NishaMaths 74 · Madurai
- CardNo
- 28
- Name
- Nisha
- Gender
- F
- DateOfBirth
- 10 Sep
- CityTown
- Madurai
- Mathematics
- 74
- Physics
- 83
- Chemistry
- 83
- Total
- 240
NaveenMaths 72 · Vellore
- CardNo
- 29
- Name
- Naveen
- Gender
- M
- DateOfBirth
- 13 Oct
- CityTown
- Vellore
- Mathematics
- 72
- Physics
- 66
- Chemistry
- 81
- Total
- 219
Try each question before revealing its answer. Trace one card at a time and state exactly what every variable means.
The Week 1 checklist
| Idea | Remember |
|---|---|
| Algorithm | Precise steps, a goal and a stopping condition. |
| Iteration | Initialize, visit each new item, update, then stop. |
| Count / sum / average | Add 1 / add the field value / divide sum by matching count. |
| Filters | AND needs both; OR needs at least one. |
| Flowchart | Terminal, process, decision and flowline. |
| Data sanity | Check format, range, relationships, context and missing values. |
| Type and subtype | Allowed values and permitted operations. |
| Representation | Keep scales, units and calendar assumptions explicit. |
| Record / list | Named fields / an ordered sequence of items. |
Twenty mixed practice questions
Try it yourself
1. Three cards have maths marks 20,40,60. Give Count and Sum after each visit.
Show explained answer
After card 1: Count=1, Sum=20. After card 2: Count=2, Sum=60. After card 3: Count=3, Sum=120. Final average = 120/3 = 40.
Try it yourself
2. Count starts at 0 and is set to 0 again for each new card before adding 1. What does it report after five cards?
Show explained answer
It reports 1 instead of 5. Initialization belongs before the loop so earlier progress is not erased.
Try it yourself
3. A filter accepts marks greater than 50. Which of 50,51,49,75 match?
Show explained answer
51 and 75. “Greater than” excludes the boundary value 50.
Try it yourself
4. In the teaching words, how many adjectives have more than four letters?
Show explained answer
bright (6) and beautiful (9) match: 2. tiny is an adjective but has only 4 letters.
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5. For the teaching marks, list IDs satisfying group F OR city Chennai.
Show explained answer
S01,S03,S04,S05,S06: five records. A record satisfying both conditions is counted only once in an OR selection.
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6. For the same dataset, list IDs satisfying group F AND city Chennai.
Show explained answer
S01 and S03: two records. Both conditions must be true.
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7. Is 30 June inside the first half of the year? What about 1 July?
Show explained answer
30 June is included; 1 July is excluded. The stated range is 1 January through 30 June, inclusive.
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8. Group A has sum 150 and count 2. Group B has sum 180 and count 3. Compare averages.
Show explained answer
A average = 150/2 = 75. B average = 180/3 = 60. B has the larger total, but A has the larger average.
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9. What is wrong with dividing FSum by the total count of all students?
Show explained answer
That mixes a filtered numerator with an unfiltered denominator. For the F-group average, divide FSum by FCount.
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10. A flowchart’s filter No branch skips the current card’s movement. What should be fixed?
Show explained answer
Make the rejected-card path mark or move the card too, then join the loop. Otherwise it may be selected repeatedly.
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11. Bills have item categories [Food,Food], [Food,Soap-category], [Stationery], [Food]. Count all-food and no-food bills.
Show explained answer
All-food = 2 (first and fourth). No-food = 1 (third). The second bill is mixed and increases neither.
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12. A bill contains 3 notebooks at Rs 25 each, but says cost Rs 70. What can you conclude?
Show explained answer
The relation fails because 3×25 = 75. At least one of quantity, unit price or cost is wrong; verify which before correcting it.
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13. A recorded date is 29 February and no year is given. Can you prove it is invalid?
Show explained answer
No. It is valid in a leap year. You need year information or an explicit calendar convention.
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14. A customer buys 250 g at Rs 80 per kg. Find the cost.
Show explained answer
250 g = 0.25 kg. Cost = 0.25×80 = Rs 20. Multiplying 250 by 80 would mix grams with a per-kilogram price.
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15. What is the result type of “card category = Verb”?
Show explained answer
Boolean: True or False. The input category is a label, but the comparison yields a truth value.
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16. What is wrong with storing a three-subject total of 240 in Marks restricted to 0–100?
Show explained answer
It is out of range for that subtype. Use TMarks or another appropriate total type that permits 240.
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17. Store Rs 19.95 and Rs 5.10 as paise, then add and display.
Show explained answer
1995 + 510 = 2505 paise, displayed Rs 25.05. Both stored values use the same scale.
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18. Does stored integer 31 always mean 1 February?
Show explained answer
Only under the specified date representation with 1 January=0. In an Amount it could mean 31 paise; representation requires its type and convention.
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19. Is “items” in ShoppingBill a single record or a list? What is one element?
Show explained answer
It is an ItemList. One element is an Item record with fields such as name, category, quantity, unit price and cost.
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20. Two records have valid field types but share an ID. Does field validation catch the full problem?
Show explained answer
Not necessarily. Each ID may be an allowed integer, while uniqueness fails across records. Add an across-record duplicate check.