Out of 3 books on Economics , 4 books on corpora's strategy and 5 books on philosophy , how many collection consisits of exactly one book on each subject ?

Options

A. 40
B. 36
C. 60
D. 120

Answer

To solve the problem of how many collections consist of exactly one book from each subject (Economics, Corporate Strategy, and Philosophy), we can follow these steps:

### Step 1: Identify the number of books in each subject
- **Economics**: 3 books
- **Corporate Strategy**: 4 books
- **Philosophy**: 5 books

### Step 2: Determine the number of choices for each subject
For each subject, we can choose one book:
- For Economics, we have 3 choices.
- For Corporate Strategy, we have 4 choices.
- For Philosophy, we have 5 choices.

### Step 3: Calculate the total number of combinations
To find the total number of collections that consist of exactly one book from each subject, we multiply the number of choices for each subject together:

\[ \text{Total Collections} = (\text{Number of Economics Books}) \times (\text{Number of Corporate Strategy Books}) \times (\text{Number of Philosophy Books}) \]

Substituting the values:

\[ \text{Total Collections} = 3 \times 4 \times 5 \]

### Step 4: Perform the multiplication
Now, we calculate:

\[ 3 \times 4 = 12 \]
\[ 12 \times 5 = 60 \]

### Conclusion
Thus, the total number of collections that consist of exactly one book on each subject is **60**.