14. Divide the sum of 18/5 and - 71/5 by their difference.

15. What should be added to (1/2+1/3+1/5) to get 4?

14. - 53/89

15. 2 29/30

Step-by-step explanation:

Sum of

18/5 + (-71/5)

=18/5-71/5

= 18-71/5

= - 53/5

Difference between 18/5 and - 71/5

=18/5 - (-71/5)

=18/5+71/5

=18+71 / 5

=89/5

Sum divided by difference

-53/5:89/5

= - 53/5*5/89

= - 53/89

15.

1/2+1/3+1/5+x=4

15+10+6/30+x=4

31/30+x=4

31/30-4=x

31-120/30=x

89/30=x

2 29/30=x