A number reduced by 37% becomes 315. By what percentage should it be increased so that it becomes 800?

Correct option is B

Given:

A number reduced by 37% becomes 315.

We need to find the percentage increase to make it 800.

Solution:
Let the original number be x.
When reduced by 37%, the number becomes 315:

x - 0.37x = 315

0.63x = 315

x $$= \frac{315}{0.63} = 500$$​

So, the original number is 500.

Now, we need to find the percentage increase that will make the number 800.
Let the percentage increase be p.
After increasing by p%, the number becomes 800:

500 +$$\frac{p}{100} \times 500 = 800$$​​

500 + 5p = 800

5p = 300

p = $$\frac{300}{5} = 60$$​

The number should be increased by 60% to become 800.