Question

There are 100 MBA aspirants in a classroom and 99% of them are engineers. How many engineers must leave the classroom in order to reduce the percentage of engineers in the classroom to 98% ?

• A. 1
• B. 2
• C. 50
• D. 90

Answer 1

The Correct Option is C

To solve this problem, let's follow these steps:

1. Determine the initial number of engineers. Since 99% of the 100 aspirants are engineers: 0.99 × 100 = 99
2. Let x be the number of engineers who leave the classroom. The remaining engineers would be 99 - x.
3. After x engineers leave, the total number of aspirants becomes 100 - x.
4. We need the percentage of engineers to be 98%, thus setting up the equation:

\[\frac{99-x}{100-x}=0.98\]

1. Solve the equation:

\[\frac{99-x}{100-x}=0.98\]

Simplify:

\[99-x=0.98(100-x)\]

Expand:

\[99-x=98-0.98x\]

Rearranging terms:

\[-x+0.98x=98-99\]

Simplify further:

\[-0.02x=-1\]

Isolating x:

\[x=\frac{-1}{-0.02}=50\]

1. Hence, 50 engineers must leave the classroom to make the percentage of engineers drop to 98%.

Therefore, the correct answer is 50.