The total age of Ravi and Ali is 10yr more than the total age of Ali and john. John is how many years younger than Ravi?

Options

A. 10
B. 20
C. cannot measured
D. none of the above

Answer

To solve the problem, let's define the ages of Ravi, Ali, and John as follows:

- Let Ravi's age be \( X \)
- Let Ali's age be \( Y \)
- Let John's age be \( Z \)

According to the problem, we have the following relationship:

1. The total age of Ravi and Ali is 10 years more than the total age of Ali and John. This can be expressed as:
\[ X + Y = (Y + Z) + 10 \]

Now, let's simplify this equation step by step.

### Step 1: Write the equation
From the relationship given, we can write:
\[ X + Y = Y + Z + 10 \]

### Step 2: Subtract \( Y \) from both sides
To simplify the equation, subtract \( Y \) from both sides:
\[ X = Z + 10 \]

### Step 3: Rearrange the equation
This equation tells us that Ravi's age \( X \) is 10 years more than John's age \( Z \). To find out how much younger John is than Ravi, we can rearrange the equation:
\[ Z = X - 10 \]

### Step 4: Conclusion
From the equation \( Z = X - 10 \), we can conclude that John is 10 years younger than Ravi. Thus:
\[ \text{John is 10 years younger than Ravi.} \]

### Final Answer
John is 10 years younger than Ravi.

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