Pre-Algebra Examples

Add 4+5+7+8+2+5+9+7+8
4+5+7+8+2+5+9+7+84+5+7+8+2+5+9+7+8
Step 1
Add 44 and 55.
9+7+8+2+5+9+7+89+7+8+2+5+9+7+8
Step 2
Add 99 and 77.
16+8+2+5+9+7+816+8+2+5+9+7+8
Step 3
Add 1616 and 88.
24+2+5+9+7+824+2+5+9+7+8
Step 4
Add 2424 and 22.
26+5+9+7+826+5+9+7+8
Step 5
Add 2626 and 55.
31+9+7+831+9+7+8
Step 6
Add 3131 and 99.
40+7+840+7+8
Step 7
Add 4040 and 77.
47+847+8
Step 8
Add 4747 and 88.
5555
 [x2  12  π  xdx ]  x2  12  π  xdx