The probability of selecting a rotten apple randomly from a heap of 900 apples is `0.18`. What is the number of rotten apples in the heap?

Answer

To find the number of rotten apples in a heap of 900 apples given that the probability of selecting a rotten apple is 0.18, we can follow these steps:

### Step 1: Understand the Probability Formula
The probability of selecting a rotten apple can be expressed using the formula:
\[ P(\text{rotten apple}) = \frac{\text{Number of rotten apples}}{\text{Total number of apples}} \]
Where:
- \( P(\text{rotten apple}) \) is the probability of selecting a rotten apple.
- Number of rotten apples is what we need to find.
- Total number of apples is given as 900.

### Step 2: Substitute the Known Values
From the problem, we know:
- \( P(\text{rotten apple}) = 0.18 \)
- Total number of apples = 900

We can substitute these values into the probability formula:
\[ 0.18 = \frac{\text{Number of rotten apples}}{900} \]

### Step 3: Solve for the Number of Rotten Apples
To find the number of rotten apples, we can rearrange the equation:
\[ \text{Number of rotten apples} = 0.18 \times 900 \]

### Step 4: Calculate the Result
Now, we perform the multiplication:
\[ \text{Number of rotten apples} = 0.18 \times 900 = 162 \]

### Conclusion
The number of rotten apples in the heap is **162**.

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