How would you use estimation to evaluate this expression 10.2 x [(2x3.7)+8]

Round off the decimals to a sensible number. So 3.7 would be 4 and 10.2 would be 10. In this case, it would be (2 × 4 + 8) × 10 which is 160.

38+105= 143, 39+104=143, and you will find then adding the numbers on opposite sides, moving inwards yields the answer 138 every time. because of this, you’re going to multiply 138 times the number of pairs, which is 34. therefore, 34*138= 4692(i’m sorry if it’s the wrong numbers, but it’s the right concept)