Question

Which of the two rational number (9/-13) or (7/-12) grater in the pairs?

Answer 1

(9/-13) or (7/-12)

First we write each of the given numbers with a positive denominator.

One number = (9/-13)

= [(9× (-1))/ (-13×-1)]

= (-9/13)

One number = (7/-12)

= [(7× (-1))/ (-12×-1)]

= (-7/12)

The LCM of the denominators 13 and 12 is 156

∴ (-9/13) = [(-9×12)/ (13×12)] = (-108/156)

and (-7/12) = [(-7×13)/ (12×13)] = (-91/156)

Now, -108 < -91

⇒ (-108/156) < (-91/156)

⇒ (-9/13) < (-7/12)

Hence, (9/-13) < (7/-12)

∴ (7/-12) is greater.