What are the directions for this?
to do it in mental math: you can ignore the zeroes in 400 for now.
4*14 = 4*10 + 4*4 = 40 + 16 = 56
now add the zeroes back on: 5600m
215% of 18
You must change 215% into a decimal by multiplying by 100 which is 2.15
Then you multiply them
2.15×18=38.7
Then you estimate to the nearest whole number
38.7⇒39
You answer is 38.7
Your answer is 39 estimated