Question

Q1. Divide the sum of 65/12 and 12/7 by their difference? Q2. The digits of a 2-digit number differ by 5. If the digits are interchanged and the resulting number is added to the original number, we get 99. Find the original number.

Answer 1

sum:
=65/12+12/7
=[65(7)+12(12)]/12(7)
=(455+144)/84
=599/84

differenc:
=65/12-12/7
=(455-144)/84
=311/84

divide:
=(599/84)/(311/84)
=599/311