A one kilogram box of chocolates costs $0.90 less than twice the cost of a box of a 500g box. Two one kilogram boxes and three 500g boxes cost $34.60. Find the cost of:
a) one kilogram box
b) 500g box.
Let x be the cost of 1kg box of chocolate. And let y be the cost of 500g box of chocolate.
Then, express the given conditions is math form.
The first condition is that the x is 0.90 less than twice y. So, its math form is:
`x=2y-0.90` (Let this be EQ1.)
And the second condition is that the cost of two x's and three y's is 34.60. So, its math form is:
`2x + 3y=34.60` (Let this be EQ2.)
To solve for x and y, apply substitution method.
So, plug-in EQ1 to EQ2.
`2x + 3y = 34.60`
Then, plug-in this value of y to EQ1.
Hence, the cost of 1kg box of chocolate is $9.50 per box and the cost of 500g box of chocolate is $5.20 per box.