The grasshopper, the frog and the mouse had a jumping contest. The grasshopper jumped 39 inches. The grasshopper jumped 19 inches farther than the frog and the mouse jumped 12 inches lesser than the frog. How far did the mouse jump?
Let's denote the frog's jump by x. Then the grasshopper's jump is x+19 and the mouse's jump is x-12. 

The information in the task can be summarized in the following equation: 

x+19=2x-12. 

Therefore the answer (numeric) is: 

x=16


Q: A man has a rectangular garden. The length of the garden is 4 times the width. The perimeter of the garden is 96 feet. Find the dimensions of the garden.

A: Let's think step by step. Introduce intermediate variables and solve the task symbolically. 

Let's denote the width of the garden by w. Then the length of the garden is 4w. 

The perimeter of the garden is the sum of the lengths of all sides. In this case it is: 

2w+4w=96. 

Therefore the answer (numeric) is: 

w=24, 4w=96