Answer: x = 10
Explanation:
Let's say that the unknown is x.
{2/5 = ?/25}
Step 1. 2/5 = x/25
Step 2. Multiply by 25 on both sides. 2/(5 * 25) = x/(25 * 25)
Step 3. 2 * 5 = x
Step 4. 10 = x
Step 5. Let's check the answer x; 2/5 = 10/25
Step 6. Simplify; 2/5 = (10/5) / (25/5)
Step 7. Check; 2/5 = 2/5
This answer is true