Which answer explains the correct way to move the decimal to find the product of 15.31 × 103?
a. two place to the left
b. three places to the right
c. three places to the left
d. four places to the right

A. two places to the left

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post