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3 years ago

Given x : y: z = 5:1:3 and z - y = 28. find the value of x + y

Mathematics

1 answer:

Vera_Pavlovna [14]3 years ago

5 0

Answer:

x + y = 84

Step-by-step explanation:

Given

x : y : z = 5 : 1 : 3, then

$\frac{x}{y}$ = 5 ( multiply both sides by y )

x = 5y ←

and $\frac{y}{z}$ = $\frac{1}{3}$ ( cross- multiply )

3y = z

Substitute z = 3y into z - y = 28

3y - y = 28

2y = 28 ( divide both sides by 2 )

y = 14 ← ←

Substitute y = 14 into x = 5y

x = 5 × 14 = 70 ← ←

Substitute y = 14 into z - y = 28

z - 14 = 28 ( add 14 to both sides )

z = 42 ← ←

Thus x = 70, y = 14 and z = 42

Hence x + y = 70 + 14 = 84

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3 years ago

Given x : y: z = 5:1:3 and z - y = 28. find the value of x + y​

Given x : y: z = 5:1:3 and z - y = 28. find the value of x + y