Help!!I need to understand how to estimate the sum or difference for fractions..2 and 2 thirds plus 3 fourths,1 and 7 eighths minus 1 and a half,and 3 and 9 tenths minus 1 and 2 fifths,please help,not good with math

Answer 1

ell 2/3 is a bit less than 3/4 but pretty close
3/4 + 3/4 = 1.5
so a bit less than 3 1/2
the real answer is very close to that:
2 2/3 + 3/4 ? = 2 8/12 + 9/12 = 2 17/12 = 3 5/12 (estimate wrong by 1/12)

Answer 2

1 7/8 - 1 1/2

well that is just the difference between 7/8 and 4/8 which is 3/8, no need to estimate

Answer 3

2 9/10 - 1 2/5
again why estimate. That is
2 9/10 - 1 4/10
which is
1 5/10
which is 1 1/2