The true statement is as follows:
The product 13 / 4 × 2 can be used to find the unit rate in cm per hour.
After one hour, the height of the candle will have decreased by 6 1 / 2 cm.
What is rate?
Rate is the ratio between two related quantities in different units.
The height of the candle decreases from 10 cm to 6 3 / 4 cm after burning for 1 / 2 hours.
6 3 / 4 cm = 27 / 4 cm
10 - 27 / 4 = 40 - 27 / 4 = 13 / 4 cm
Therefore, 13 / 4 cm of candles were lost in 1 / 2 hours.
Rate = 13 / 4 × 2 = 26 / 4 = 13 / 2 cm per hour
Therefore, the product 13 / 4 × 2 can be used to find the unit rate in cm per hour.
13 / 4 + 13 / 4 = 13 + 13/ 4 = 26 / 4 = 13 / 2 = 6 1 / 2 cm.
Therefore, after one hour, the height of the candle will have decreased by 6 1 / 2 cm.
learn more on rate here: https://brainly.com/question/18188023
