Answer
the estimated sum is 11.59
And the estimated difference is
0.32
Step-by-step explanation:
The question bothers to know how well you understand your fraction
In a step by step approach we will estimate both the sum and the difference
Step one
Let us know what the sum is
8/9+4/7
The Lcm can be gotten by multiplying the denominators
9x7=63
56+36/63= 92/63
=11.59
Hence the estimated sum is 11.59
Step two
Let us estimate the difference also we have
8/9-4/7
Like before our Lcm =63
56-36/63=20/63
=0.32
Our estimated difference is 0.32