Answer:
12. 1 1/14 or 15/14
13. 37/24 or 1 13/24
14. 11/9 or 1 2/9
15. 26/21 or 1 4/26 or 1 2/13
Find LCD
multiply denominators
7 × 2 = 14
14 will be our common denominator
Convert fractions
divide 14 by the denominators, then multiply the quotient to the numerator.
14 ÷ 7 = 2
2 × 4 = 8
8 will be the numerator
14 ÷ 2 = 7
7 × 1 = 7
7 will be the numerator
Arrange
8/14 + 7/14
Add the numerators, then copy the denominator
8 + 7/14 = 15/14
Simplify
15 ÷ 14
= 1 remainder 1
1 1/14
Answer
15/14 or 1 and 1/14