Respuesta :

Okay well remember this. 4 or less let it rest, 5 or more let it sore. So 33, 3 is less than 4 so to would round it down to 30. Now 89, 9 is greater than 5 so we round it up to 90. Now simply add 30 and 90. 30+90=120. The estimated sum is 120.