Norman and his two brothers have 25 toy cars. 8/25 of them belong to his younger brother and 9/25 belong to his elder brother. How many cars does Norman have?

Steps to Solve

1. Identify total number of cars

The total number of toy cars is given as 25.

2. Calculate younger brother's cars

To find how many cars the younger brother has, use the given fraction:

$$ \text{Younger brother's cars} = \frac{8}{25} \times 25 $$

Calculating this gives:

$$ \frac{8}{25} \times 25 = 8 $$

3. Calculate elder brother's cars

Next, calculate how many cars the elder brother has:

$$ \text{Elder brother's cars} = \frac{9}{25} \times 25 $$

Calculating this gives:

$$ \frac{9}{25} \times 25 = 9 $$

4. Calculate Norman's cars

Now, to find how many cars Norman has, subtract the number of cars owned by both brothers from the total number of cars:

$$ \text{Norman's cars} = 25 - (\text{Younger brother's cars} + \text{Elder brother's cars}) $$

Substituting the values gives:

$$ \text{Norman's cars} = 25 - (8 + 9) $$

5. Final calculation for Norman's cars

Now perform the final subtraction:

$$ \text{Norman's cars} = 25 - 17 = 8 $$