Question

At the school store the cost of three markers and two pencils is exactly $2.20 while the cost of four markers and six pencils is exactly $3.40. How much would it cost to buy 1 marker and 2 pencils?

Answer 1

Answer:

$\ 0.92$

Step-by-step explanation:

Let cost of 1 marker be $x$ and 1 pencil be $y$

From the question we get two equations

$3x+2y=2.2\quad ...(i)$

$4x+6y=3.4\quad ...(ii)$

Multiply the first equation by 3 $(i)\times3$

$9x+6y=6.6\quad ...(iii)$

$4x+6y=3.4\quad ...(iv)$

Subtracting the above equations $(iii)-(iv)$ we get

$5x=3.2\\\Rightarrow x=\dfrac{3.2}{5}\\\Rightarrow x=0.64$

$4x+6y=3.4\\\Rightarrow y=\dfrac{3.4-4x}{6}=\dfrac{3.4-4\times 0.64}{6}\\\Rightarrow y=0.14$

One marker costs $0.64 and one pencil costs $0.14

Cost of 1 marker and 2 pencils is $0.64+0.14\times 2=\ 0.92$.