A bax has 100 blue balls, 50 red balls, 50 black balls. 25% of blue balls and 50% of red balls are taken away. Percentage of black balls at present is

Options

A. 0.5
B. 0.25
C. 33 `1/3`%
D. 0.4

Answer

To solve the problem step by step, we will first determine how many balls are left after the specified percentages are taken away and then calculate the percentage of black balls in relation to the total number of balls remaining.

**Step 1: Determine the initial counts of the balls.**
- Blue balls = 100
- Red balls = 50
- Black balls = 50

**Step 2: Calculate the number of blue balls taken away.**
- 25% of blue balls = 25% of 100 = (25/100) * 100 = 25 blue balls are taken away.
- Remaining blue balls = 100 - 25 = 75 blue balls.

**Step 3: Calculate the number of red balls taken away.**
- 50% of red balls = 50% of 50 = (50/100) * 50 = 25 red balls are taken away.
- Remaining red balls = 50 - 25 = 25 red balls.

**Step 4: Determine the total number of balls remaining.**
- Remaining blue balls = 75
- Remaining red balls = 25
- Remaining black balls = 50 (no black balls were taken away)

Total remaining balls = 75 (blue) + 25 (red) + 50 (black) = 150 balls.

**Step 5: Calculate the percentage of black balls.**
- Number of black balls = 50
- Total number of balls = 150

Percentage of black balls = (Number of black balls / Total number of balls) * 100
= (50 / 150) * 100
= (1/3) * 100
= 33.33%

**Final Answer:**
The percentage of black balls at present is 33.33%.

---