Question

Arrange `5/8, -3/16, -1/4 and 17/32` in descending order of their magnitudes.
Also, find the sum of the lowest and largest of these fractions. Express the result obtained as a decimal fraction correct to two decimal places.

Answer 1

Consider the given numbers : `5/8, -3/16, -1/4 and 17/32`
The LCM of 8, 16, 4 and 32 is 32.
Thus, the given numbers are given below :
`5/8, -3/16, -1/4 and 17/32`

= `[ 5 xx 4 ]/[ 8 xx 4 ], - [ 3 xx 2 ]/[ 16 xx 2 ], - [ 1 xx 8 ]/[ 4 xx 8 ] and [ 17 xx 1 ]/[ 32 xx 1 ]`

= `20/32, -6/32, -8/32, and 17/32`

Thus, the numbers in descending order are shown below :

`20/32, 17/32, -6/32 and -8/32`

Thus, the given numbers in descending order are listed below :

`5/8, 17/32, -3/16 and -1/4`.

We need to find the sum of the largest and smallest of the above numbers.

Thus, sum = `5/8 + ( - 1/4)`

= `5/8 - 1/4`

= `5/8 - [ 1 xx 2 ]/[ 4 xx 2 ]`

= `5/8 - 2/8`

= `3/8`

We need to express this fraction as a decimal, correct to two decimal places.
Thus, we have `3/8` = 0.375 ≈ 0.38.