Question

If y is 2.5 when x is 5 and i varies directly with x, find y when x is 14 ?

Answer 1

ANSWER

$y = 7$

EXPLANATION

If y varies directly with x, we write the mathematical statement;

$y \propto \: x$

When we introduce the constant of proportionality k, then we write the equation,

$y = kx$

If y is 2.5 when x is 5,then we have;

$2.5 = 5k$

$k = \frac{2.5}{5}$

$k = 0.5$

The equation of variation then becomes;

$y = 0.5x$

when x=14,

$y = 0.5(14)$

$y = 7$

Answer 2

Answer:

The correct answer is, y = 7

Step-by-step explanation:

It is given that,If y is 2.5 when x is 5 and i varies directly with x

To find the relationship between x and y

From the given data, we can write,

x = 5 the y = 2.5

2.5 = 5/2

Therefore y = x/2

To find the value of y

x = 14

y = x/2 = 14/2 = 7

Therefore the correct answer is, y = 7