Arrange the following in the descending order 23 - 21 ) , ( 19 - 17 ) , ( 21 - 19 .

19 - 17 ) > ( 21 - 19 ) > ( 23 - 21

23 - 21 ) > ( 21 - 19 ) > ( 19 - 17

23 - 21 ) > ( 19 - 17 ) > ( 21 - 19

21 - 19 ) > ( 23 - 21 ) > ( 19 - 17

Given expression: 10 . 0489 Group the digits before and after the decimal point in pairs. Before the decimal point, grouping is to be done from right to left. After the decimal point, grouping is to be done from left to right. Using long division method, we may find the square root of the given number as shown below. 3 . 1 7 3 1 0 . 0 4 8 9 3 - 9 6 1 1 0 4 1 - 6 1 6 2 7 4 3 8 9 7 - 4 3 8 9 0 ∴ 10 . 0489 = 3 . 17 Hence, t he square root of number is 3 . 17

Given expression: 75 . 69 Group the digits before and after the decimal point in pairs. Before the decimal point, grouping is to be done from right to left. After the decimal point, grouping is to be done from left to right. Using long division method, we may find the square root of the given number as shown below. 8 . 7 8 7 5 . 6 9 8 - 6 4 1 6 7 1 1 6 9 7 - 1 1 6 9 0 ∴ 75 . 69 = 8 . 7 Hence, t he square root of number is 8 . 7

Given expression: 0 . 2916 Group the digits before and after the decimal point in pairs. Before the decimal point, grouping is to be done from right to left. After the decimal point, grouping is to be done from left to right. Using long division method, we may find the square root of the given number as shown below. 0 . 5 4 5 0 . 2 9 1 6 5 - 2 5 1 0 4 4 1 6 4 - 4 1 6 0 ∴ 0 . 2916 = 0 . 54 Hence, t he square root of number is 0 . 54

Given expression: 156 . 25 Group the digits before and after the decimal point in pairs. Before the decimal point, grouping is to be done from right to left. After the decimal point, grouping is to be done from left to right. Using long division method, we may find the square root of the given number as shown below. 1 2 . 5 1 1 5 6 . 2 5 1 - 1 2 2 0 5 6 2 - 4 4 2 4 5 1 2 2 5 5 - 1 2 2 5 0 ∴ 156 . 25 = 12 . 5 Hence, t he square root of number is 12 . 5