#### Number System Book Back Questions

7th Standard EM

Reg.No. :
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Maths

Time : 00:45:00 Hrs
Total Marks : 30
3 x 1 = 3
1. (-10)+(+7)=____

(a)

+3

(b)

-3

(c)

-17

(d)

+17

2. (-100)-0+100=_____

(a)

200

(b)

0

(c)

100

(d)

-200

3. 11×(–1)=_____

(a)

-1

(b)

0

(c)

+1

(d)

–11

4. 3 x 1 = 3
5. ____$\times$ 75=0

()

0

6. ____+(-22)=0

()

22

7. 75+(-25)=__

()

50

8. 4 x 1 = 4
9. 8 × (−4) = 32

(a) True
(b) False
10. (−30)÷(−6) =−6

(a) True
(b) False
11. (−64)÷(-64) IS 0

(a) True
(b) False
12. The sum of a positive integer and a negative integer is always a positive integer.

(a) True
(b) False
13. 3 x 2 = 6
14. Find 5 pairs of integers that add up to 2.

15. When Kala woke up, her body temperature was 102°F. She took medicine for fever. After 2 hours it was 2°F lower. What was her temperature then?

16. A student was asked to subtract (–12) from (–47). He got−30.Is he correct? Justify.

17. 3 x 3 = 9
18. Add (i) (–40) and (30) (ii) 60 and (–50)

19. Prove that (–7) × (+8) is an integer and mention the property.

20. Are 3 × [(–4)+6] and [3 ×(–4)]+(3×6) equal? Mention the property.

21. 1 x 5 = 5
22. The temperature at Srinagar was −3°C on Friday. If the temperature decreases by 1°C next day, then what is the temperature on that day?