A worker is installing blue and white square tiles in a kitchen. Blue tiles have different lengths than white tiles. A row of 8 blue tiles and 16 white tiles has a length of 39 inches. A row of 40 blue tiles and 8 white tiles has a length of 42 inches. Write a system of equations that represents in inches the relationship between the length of a blue tile and the length of a white tile.

8x+16y = 39 and 40x+8y = 42 are the system of equations that represents in inches the relationship between the length of a blue tile and the length of a white tile.

Step-by-step explanation:

Let 'x' be the inches of a blue tile.

Let 'y' be the inches of a white tile.

8x+16y = 39  (1)

40x+8y = 42  (2)

Multiply eqn(2) by 2 and subtract it from eqn(1)

    8x+16y = 39

(-) 80x+16y = 84

  -72x = -45      

⇒ x = -45/-72

⇒ x = 5/8

∴ Blue tile is 5/8 inches.

substitute x=5/8 in eqn(1)

⇒ 8(5/8) + 16y = 39

⇒ 16y = 39-5

⇒ y =34/16

⇒ y = 17/8

∴ White tile is 17/8 inches.

36 girls

step-by-step explanation:

the 48 boys is 4 parts of the ratio

divide 48 by 4 to obtain one part of the ratio

= 12 ← 1 part of the ratio

3 parts = 3 × 12 = 36 ← number of girls

sinn is the total amount of students now and m were the students before, you subtract them both (n-m) and divide that by m. then, since to get a percentage from a fraction you have to multiply by 100, your answer should look like this: n-m/m*100

step-by-step explanation: