Arithmetic Expressions Class 7 Long Question Answer

Arithmetic Expressions Class 7 Long Question Answer

Arithmetic Expressions Class 7 Long Question Answer

Question 1.

Find the value of the expression 12 - 15 + 4 + 9 × 5 + 4 ÷ 2 + 6 - 3 × 5.

Solution:

Value = 12 - 15 + 4 + 45 + 2 + 6 - 15

= -3 + 49 + 8 - 15

= 46 + 8 - 15

= 54 - 15 = 39.

Question 2.

Find the value of the expression 4 - 4 + 4- 4 + 4 - 4 + 4 - 4 + 4 - 4 + ... for

(a) even number of terms.

Solution:

For even number of terms, we have 4 - 4 + 4 - 4 + 4 - 4 + 4 - 4 + ...

= (4 - 4) + (4 - 4) + (4 - 4) + (4 - 4) + ...

= 0 + 0 + 0 + 0 + 0 + ... = 0

(b) odd number of terms.

Solution:

For odd number of terms, we have (4 - 4) + (4 - 4), + (4 - 4) + (4 - 4) + ... + ... + (-4)

= 0 + 0 + 0 + 0 + 0 + ... + (-4)

= 0 + (-4) = -4.