I'll solve all the problems step by step for each day.
## MONDAY
1.
12 × 11 =
- 12 × 10 = 120
- 12 × 1 = 12
- 120 + 12 = 132
2.
81 ÷ 9 =
- 9 × 9 = 81
- Answer: 9
3.
48 + 78 =
- 40 + 70 = 110
- 8 + 8 = 16
- 110 + 16 = 126
4.
114 - 64 =
- 114 - 60 = 54
- 54 - 4 = 50
5.
The time is 8:30pm. What time is it in 90 minutes?
- 90 minutes = 1 hour and 30 minutes
- 8:30pm + 1 hour = 9:30pm
- 9:30pm + 30 minutes = 10:00pm
6.
1/6 of 36 =
- 36 ÷ 6 = 6
7.
What fraction of the shape is shaded? (3 blue squares out of 6 total)
- 3/6 = 1/2
8.
Round to nearest 100 - 145 =
- 145 is closer to 100 than 200
- Answer: 100
9.
How many cm in 1m?
- Answer: 100
10.
89, 94, 99, ___
- Pattern: adding 5 each time
- 99 + 5 = 104
## TUESDAY
1.
9 × 8 =
- Answer: 72
2.
64 ÷ 8 =
- 8 × 8 = 64
- Answer: 8
3.
205 + 115 =
- 200 + 100 = 300
- 5 + 15 = 20
- 300 + 20 = 320
4.
350 - 120 =
- 350 - 100 = 250
- 250 - 20 = 230
5.
The time is 7:00am. What time is it in 65 minutes?
- 65 minutes = 1 hour and 5 minutes
- 7:00am + 1 hour = 8:00am
- 8:00am + 5 minutes = 8:05am
6.
2/3 of 18 =
- 18 ÷ 3 = 6
- 6 × 2 = 12
7.
What fraction of the shape is shaded? (2 green squares out of 6 total)
- 2/6 = 1/3
8.
Round to nearest 100 - 318 =
- 318 is closer to 300 than 400
- Answer: 300
9.
How many cm in 3.5m?
- 3.5 × 100 = 350
10.
1.2, 1, 0.8, ___
- Pattern: subtracting 0.2 each time
- 0.8 - 0.2 = 0.6
## WEDNESDAY
1.
12 × 7 =
- 10 × 7 = 70
- 2 × 7 = 14
- 70 + 14 = 84
2.
49 ÷ 7 =
- 7 × 7 = 49
- Answer: 7
3.
69 + 81 =
- 60 + 80 = 140
- 9 + 1 = 10
- 140 + 10 = 150
4.
83 - 41 =
- 80 - 40 = 40
- 3 - 1 = 2
- 40 + 2 = 42
5.
The time is 1:40pm. What time is it in 25 minutes?
- 1:40pm + 20 minutes = 2:00pm
- 2:00pm + 5 minutes = 2:05pm
6.
2/5 of 40 =
- 40 5 = 8
- 8 × 2 = 16
7.
What fraction of the shape is shaded? (5 yellow squares out of 6 total)
- Answer: 5/6
8.
Round to nearest 100 - 1,589 =
- 1,589 is closer to 1,600 than 1,500
- Answer: 1,600
9.
How many m in 100cm?
- 100 ÷ 100 = 1
10.
75, 90, 105, ___
- Pattern: adding 15 each time
- 105 + 15 = 120
## THURSDAY
1.
6 × 6 =
- Answer: 36
2.
110 ÷ 10 =
- Answer: 11
3.
14 + 28 =
- 10 + 20 = 30
- 4 + 8 = 12
- 30 + 12 = 42
4.
27 - 13 =
- 27 - 10 = 17
- 17 - 3 = 14
5.
The time is 9:30am. What time is it in 80 minutes?
- 80 minutes = 1 hour and 20 minutes
- 9:30am + 1 hour = 10:30am
- 10:30am + 20 minutes = 10:50am
6.
1/8 of 64 =
- 64 ÷ 8 = 8
7.
What fraction of the shape is shaded? (2 dark squares out of 6 total)
- 2/6 = 1/3
8.
Round to nearest 100 - 7,962 =
- 7,962 is closer to 8,000 than 7,900
- Answer: 8,000
9.
How many m in 250cm?
- 250 ÷ 100 = 2.5
10.
1.8, 2.1, 2.4, ___
- Pattern: adding 0.3 each time
- 2.4 + 0.3 = 2.7
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Final Answer:
MONDAY: 1. 132, 2. 9, 3. 126, 4. 50, 5. 10:00pm, 6. 6, 7. 1/2, 8. 100, 9. 100, 10. 104
TUESDAY: 1. 72, 2. 8, 3. 320, 4. 230, 5. 8:05am, 6. 12, 7. 1/3, 8. 300, 9. 350, 10. 0.6
WEDNESDAY: 1. 84, 2. 7, 3. 150, 4. 42, 5. 2:05pm, 6. 16, 7. 5/6, 8. 1,600, 9. 1, 10. 120
THURSDAY: 1. 36, 2. 11, 3. 42, 4. 14, 5. 10:50am, 6. 8, 7. 1/3, 8. 8,000, 9. 2.5, 10. 2.7
Parent Tip: Review the logic above to help your child master the concept of mental arithmetic worksheet.
