a) 7/10[d +5/6] = 7, multiply both sides by 10 / 7
[d + 5/6] = 10
[6d + 5] / 6 = 10 cross multiply
6d + 5 = 60 subtract 5 from both sides
6d =55 divide both sides by 6
d = 55 / 6
b)
5c/4 - 2c/3 =7/10 Put the LHS over the CD=12
[15c - 8c] /12 = 7/10
7c / 12 = 7/10 cross multiply
7c = 84/10 divide both sides by 7
c =84 / 10 x 1/7
c = 84 / 70 divide both sides by 14
c = 6/5
