Answer:
number of bricks = 16 and number of blocks = 12
Step-by-step explanation:
From given information it seems , we need to determine number of bricks and number of blocks.
lets assume number of bricks = x
and number of blocks = y
since total items in brickyard is 28
⇒ number of bricks + number of blocks = 28
⇒ x + y = 28 ----------------------- equation 1
Given that cost of 1 brick = $0.38 and cost of 1 block =$1.56
so cost of x bricks = cost of 1 brick × x = 0.38x
And cost of y blocks = cost of 1 block × y = 1.56y
total cost of 28 items order = $24.80
total cost of 28 items = cost of x bricks + cost of y blocks
⇒0.38x + 1.56y = 24.80 ----------------equation 2
Now we are having following two equations
x + y = 28 ----------------------- equation 1
0.38x + 1.56y = 24.80 ----------------equation 2
from equation 1 we get x = 28 - y , substituting this value of x in equation 2 we get
0.38(28 - y) + 1.56y = 24.80
⇒10.64-0.38y+1.56y= 24.80
⇒1.18y = 24.80 - 10.64
⇒y = 14.16÷1.18 = 12
substituting value of y in equation 1 we get
x + 12 = 28
⇒x = 16
hence number of bricks = x = 16 and number of blocks = y = 12
