The isotopes of an element have mass numbers, `A,A+1,A+2`. The ratio of abundance of these isotopes is `3:2:4`. Calcualte the average atomic mass of the element.

Explanation

To calculate the average atomic mass of the element with isotopes having mass numbers \( A, A+1, A+2 \) and the ratio of their abundances as \( 3:2:4 \), we can follow these steps:

### Step 1: Identify the mass numbers and their respective abundances
- The isotopes have mass numbers:
- Isotope 1: \( A \) (abundance = 3)
- Isotope 2: \( A + 1 \) (abundance = 2)
- Isotope 3: \( A + 2 \) (abundance = 4)

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