Explanation/Answer:
To convert, we need a common denominator.
So if, say, we multiply the denominator by 2, we must multiply the numerator by 2 as well.
1) 4/5+4/7
4x7/5x7 + 4x5/7x5
28/35+20/35
(Both have common denominators so we can add them)
28 +20/35= 48/35=1 13/35
2) 1/2+11/8
(We already have common denominator in one of the numbers so we only have to convert ONE of the fractions)
1x4/2x4+11/8
4/8+11/8=15/8= 1 7/8
3) 1/5+1/3
1x3/5x3+1x5/3x5
3/15+5/15=8/15
Hope this helped :D
