185+415 = 200+400 = 600
It is easy to add 600+274 in your head
while waiting in the checkout line at the grocery store you add the prices up of your 3 items to make sure you have enough money.explain how to use mental math and the properties of addition to find the total costs of 3 items if the prices are $1.85, $2.74, $4.15. find the total costs.
2 answers
Using mental math, I'd add 2 + 3 + 4 to estimate that the purchase total about $9.00.