how do you know where to place the decimal point in the quotient when dividing adecimal by a whole number

Type the correct answer in each box. use numerals instead of words. if necessary, use / for the fraction bar. consider the given table.

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?

The figure shows the front side of a metal desk in the shape of a trapezoid. what is the area of this trapezoid? 10 ft²16 ft²32 ft²61 ft²