Question

Estimate each of the follwoing by rounding off each number to nearest tens:
(a) 11963 – 9369
(b) 76877 – 7783
(c) 10732 – 4354
(d) 78203 – 16407

Answer 1

(a)11963-9369=2590 
(B)76877-7783=69100
(C)10732-4354=6380
(d)78203-16407=61790.

Answer 2

(a) 11963 – 9369  

Rounded off 11963 to nearest thousands = 12000.

Rounded off 9369 to nearest hundreds = 9400.  

So, estimated sum = 12000+9400 = 21400

(b) 76877 – 7783

Rounded off 76877 to nearest hundreds =76900.

Rounded off 7783 to nearest hundreds = 7800.

So, estimated sum = 76900-7800=69100.

(c) 11244 + 3507

Rounded off 11244 to nearest hundreds = 11200.

Rounded off 3507 to nearest hundreds = 3500.  

So, estimated sum = 11200 + 3500= 14700.

(d) 17677 + 13589

Rounded off 17677 to nearest hundreds = 17700.

Rounded off 13589 to nearest hundreds = 13600.  

So, estimated sum = 17700 + 13600= 31300 .