Question

a 2×2 grid (table) with numbers: bottom - left cell is 30, bottom - right cell is 35, top - right cell is 28, and top - left cell is blank. vertical and horizontal lines are drawn around the grid.

Explanation:

Step1: Find GCD of 30 and 35

First, find the greatest common divisor (GCD) of 30 and 35. The factors of 30 are 1, 2, 3, 5, 6, 10, 15, 30. The factors of 35 are 1, 5, 7, 35. So, GCD(30, 35) = 5. Then, 30 ÷ 5 = 6 and 35 ÷ 5 = 7.

Step2: Find the missing number

Now, we know that the ratio of the bottom row is 6:7 (from 30:35). Let the missing number be \( x \). The ratio of the top row should also be 6:7, so \( \frac{x}{28} = \frac{6}{7} \). Cross - multiply: \( 7x = 28\times6 \). Then, \( 7x = 168 \), and \( x=\frac{168}{7}=24 \).

Answer:

24