Respuesta :

Answer:

Step-by-step explanation:

1) Number of white chocolate bars = x

Number of dark chocolate bars = y

Total bars = 15

x + y = 15 --------------(I)

Total cost = Php. 340

20x + 25y = 340 ----------------(II)

2)  We can use elimination method to solve this equations.

Multiply equation (I) by (-20) and then add the equations.

(I)* (-20)          -20x  -20y = - 300

(II)                    20x + 25y = 340     {Now add and x will be eliminated}

                                  5y = 40

                                    y = 40/5

y = 8

Substitute y = 8 in equation (I)

x + 8 = 15

      x = 15 - 8

x = 7

3) Number of dark chocolate bars = 8