Question

If the cost of a pencil is ₹ $(x+5)$ and that of an eraser is ₹ $x$, then how do we represent the statement:
"The total cost of 5 pencils and 10 erasers is ₹ 100" in the form of a linear equation in $x$?

• A. $5x+10(x+5)=100$
• B. $5x+10x=100$
• C. $5(x+5)+10(x+5)=100$
• D. $5(x+5)+10x=100$

Answer 1

The correct option is D

$5(x+5)+10x=100$

The cost of 5 pencils is $5\times (x+5)=5(x+5)$.
The cost of 10 erasers is $10\times x=10x$.
Thus, $5(x+5)+10x=100$