Question

Estimate each of the following sum to its nearest tens : (a) 67 +40 (b) 78 + 43 (c) 881 +728 ​

Answer 1

Answer:

1=107

2=121

3=1609

4=999

Step-by-step explanation:

Answer 2

Answer:

       (a) $67+40$ = $107$

        In $107$, Unit digit is $7$, hence it is rounded off to $110$.

        (b) $78+43$ = $121$

       In $121$, unit digit is $1$, hence it is rounded off to $120$.

        (c) $881+728$ = $1609$

       In $1609$, Unit digit is $9$, hence it is rounded off to $1610$.

Step-by-step explanation:

Given : (a) $67+40$

           (b) $78+43$

           (c) $881+728$

To find : Estimate each of the above sum to its nearest tens.

Solution :

• We know that the number when rounded off to nearest , then if it contains a unit digit number ranging between $0-4$ or $>5$, then the number is nearest to '$0$' and if the unit digit is $5-9$, then it is rounded off to nearest $10$.

• Now,

        (a) $67+40$ = $107$

        In $107$, Unit digit is $7$, hence it is rounded off to $110$.

        (b) $78+43$ = $121$

       In $121$, unit digit is $1$, hence it is rounded off to $120$.

        (c) $881+728$ = $1609$

       In $1609$, Unit digit is $9$, hence it is rounded off to $1610$.