The basic facts she used to help her estimate are (c) 28 + 7 and (d) 30 + 5
What are estimates?
Estimates are approximated calculations that are used in place of an actual calculation
The expression is given as:
28 + 7
When the numbers are approximated to the nearest 5, we have:
30 + 5
Hence, the basic facts she used to help her estimate are (c) 28 + 7 and (d) 30 + 5
Read more about estimations at:
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