Question

If a given number is increased by 25% , the number becomes 320. The given number is

• A. 286
• B. 264
• C. 276
• D. 256

Hint:

An increase of 25% is equivalent to multiplying the original number by $\frac{5}{4}$.
To find the original number, simply multiply the final number by its reciprocal: $320 \times \frac{4}{5} = 64 \times 4 = 256$.

Answer 1

The Correct Option is D

Step 1: Set up the equation.
Let the original number be x. Increasing it by 25% means multiplying by 1.25, so: 1.25x = 320.
Step 2: Solve for x.
\[ x = \frac{320}{1.25} = \frac{320 \times 4}{5} = \frac{1280}{5} = 256 \]
Step 3: Verify.
256 + 25% of 256 = 256 + 64 = 320. Correct! \[ \boxed{256} \]