So, mental math is when you...

Explain the ways you solve the problem without using pencils and stuff. Im so confused..

Here are some problems...

Use mental math to simplify each expression.

1. 8½ + 4⅓ + 2½ + 2⅔

2. Suppose you buy some camping supplies. You purchase waterproof matches for $3.95, a compass for $18.25, flashlight batteries for $3.75, and a map for $2.05. Find the total cost of the supplies.

Mental math means you need to find a short cut so that you can get it done mentally.
1. 8½ + 4⅓ + 2½ + 2⅔ = 8+4+2+2+(½+½)+(⅓+⅔) = 18

2. 3.95+18.25+3.75+2.05 = 3.95+2.05 + 18.25+3.75 = 6 + 22 = $28

So for the first one 8 1/2 + 2 1/2=11 and 4 1/3 + 2 2/3 = 7 so 11+7 =18 for the second one do the same thing 18.25 and 3.75 are easy to add then add the other two values and it becomes 1st grade addition

1. regroup in your head to
8+2=10
4+2=6
1/2+1/2=1
2/3+1/3=1
add all answers together=18

2. Also regroup:
18+2=20
3+3=6
.75+.25=1
.95+.05=1
add the answers together=$28

can predick to the future