Makayla went to the grocery store and bought 2 loaves of bread and 6 yogurts. Before tax, her total came to $12.38.
Kim went to the same grocery store and bought 1 loaf of bread and 7 yogurts. Before tax, her total came to $11.11.
How much will it cost to buy 3 loaves of bread and 2 yogurts at that same grocery store?

Respuesta :

Answer:

  $9.96

Step-by-step explanation:

The initial purchases can be formulated using the equations ...

  2b +6y = 12.38

  1b + 7y = 11.11

where b and y represent the cost of bread and yogurt, respectively.

Subtracting the first equation from 2 times the second gives ...

  2(1b +7y) -(2b +6y) = 2(11.11) -(12.38)

  8y = 9.84

  y = 1.23 . . . . . the cost of one yogurt

Substituting into the second equation gives ...

  b + 7(1.23) = 11.11

  b = 2.50 . . . . . . . . subtract 8.61

Then the cost of the desired purchase is ...

  3b +2y = 3(2.50) +2(1.23) = 7.50 +2.46 = 9.96

The cost of 3 loaves and 2 yogurts is $9.96.