Estimate the product to the nearest tens
671×32=
8 409×573=
7 045×605=
Estimate the product to the nearest hundreds
564×515=
6 757×480=
4 935×258=
Estimate the product to the highest place value
5 068×704=
4 730×660=
8 423×648=
8 512×863=
Answers
(A) Estimate the product to the nearest tens:
(i) 671×32=
The nearest tens of 671 is 670 and 32 is 30.
The product of 670×30 =20,100
(ii) 8409×573=
The nearest tens of 8409 is 8410 and 573 is 570
The product of 8410×570 = 47,93,700
(iii) 7045×605=
The nearest tens of 7045 is 7040 and 605 is 600
The product of 7040×600 =42,24,000
(B) Estimate the product to the nearest hundreds:
(i)564×515=
The nearest hundreds of 564 is 570 and 515 is 510
The product of 570×510 =2,90,700
(ii)6757×480=
The nearest hundreds of 6757 is 6700 and 480 is 500
The product of 6700×500 =33,50,000
(iii)4935×258=
The nearest hundreds of 4935 is 4900 and 258 is 200
The product of 4900×200 =9,80,000
(C) Estimate the product to the highest place value:
(i)5068×704=
5068 is rounded as 5100 and 704 as 700
The product of 5100×700 =35,70,000
(ii)4730×660=
4730 is rounded as 4700 and 660 as 700
The product of 4700×700 =32,90,000
(iii)8423×648=
8423 is rounded as 8400 and 700 as 700
The product of 8400×700 =58,80,000
(iv)8512×863=
8512 is rounded as 8500 and 863 as 870
The product of 8500×870 =73,95,000
Estimating or rounding off a number can be done in this manner - whether the last digit of a number is less than 5, we will consider it the same tens (i.e. rounding off 73 to 70), but when the last digit of a number is more than 5 we will consider it to its next tens (i.e. 78 to 80)
Now, we will estimate the product to the nearest tens ;
a. 671 × 32 =
we will round off 671 as 670 and 32 as 30
∴ 670 × 30 =20100
b. 8409 × 573=
we will round off 8409 as 8410 and 573 as 570
∴ 8410 × 570 =4793700
c. 7045 × 605=
∴ 7050 × 610 = 4300500
Estimate the product to the nearest hundreds
a. 564 × 515=
∴ 560 × 520 =291200
b. 6757 × 480=
∴ 6760 × 480 = 3244800
c. 4935 × 258=
∴ 4940 × 260 = 1284400
Estimate the product to the highest place value
a. 5068 × 704 =
∴ 5070 × 700 = 3549000
b. 4730 × 660 = 3121800
c. 8423 × 648=
∴ 8420 × 650 = 5473000
d. 8512 × 863 =
∴ 8510 × 860 = 7318600