The knocking behaviour of a fuel with octane number 60 is the same as the mixture containing ...............% iso-octane and ..............% n-heptane.

Explanation

To determine the percentages of iso-octane and n-heptane in a mixture that has the same knocking behavior as a fuel with an octane number of 60, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Octane Number**: The octane number of a fuel is a measure of its ability to resist knocking during combustion. It is defined by comparing the fuel's performance to a mixture of iso-octane and n-heptane.

2. **Know the Reference Fuels**: Iso-octane (2,2,4-trimethylpentane) is assigned an octane number of 100, while n-heptane is assigned an octane number of 0. The octane number of a fuel can be calculated based on the percentage of these two components in a mixture.

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