10th Class Mathematics Pair of Linear Equations in Two Variables Question Bank MCQs - Pair of Linear Equations in Two Variables

Aruna has only Rs.1 and Rs.2 coins with her. If the total number of coins that she has 50 and the amount of money with her is Rs.75, then the number of Rs.1 and Rs.2 coins are, respectively. (NCERT EXEMPLAR)

A) 35 and 15

B) 35 and 20

C) 15 and 35

D) 25 and 25

Correct Answer: D

Solution :

[d] Let the number of Rs.1 coins = x

and number of Rs,2 coins =y

According to the question,

\[x+y=50\] ...(1)

and\[(x\times 1)+(y\times 2)=75\Rightarrow x+2y=75\] ...(2)

Subtracting eq. (1) from eq. (2), we get

\[y=25-50=25\]

From eq. (1), \[x+25=50\Rightarrow x=25\]