Given:
Each time Sally waters her tomato plants she uses 5 liters of water.
Sally waters her tomato plants 3 times a week.
To find:
How much water, in liters, does Sally use in a week?
Solution:
We have,
Water used in each time = 5 liters
Number of times Sally waters her tomato plants = 3 times
Now,
Water used in 1 time = 5 liters
Water used in 3 time = 3×5 liters
= 15 liters
Therefore, the Sally use 15 liters of water in a week.