10 people went to a restaurant to have a meal as a group. Of these, 9 had already contributed Rs 400 each, while the 10th person had to give the entire additional amount required to honour the restaurant's bill. How much did this person pay if he had to pay Rs 900 more than the group's average?
Explanation
To solve the problem presented in image_808c7b.png, we apply the algebraic method using the concept of averages.
Step 1: Set up the variables
Let the average amount paid by the 10 people be x.
Consequently, the total bill amount paid by all 10 people is 10x.
Step 2: Formulate the equation
We know that 9 people paid Rs 400 each, and the 10th person paid Rs 900 more than the average (x+900).
The total amount equation is:
10x=(9×400)+(x+900)
Step 3: Solve for x
Simplify the equation:
10x=3600+x+900
10x−x=4500
9x=4500
x=94500
x=500
Step 4: Calculate the payment of the 10th person
The 10th person paid Rs 900 more than the average (x):
Payment=x+900
Payment=500+900=1400
The 10th person paid Rs 1400.
Correct Answer: Option 3