Variation

Which is an example of a direct variation?

• xy = 10

• y =  $\frac{2}{x}$  

• y = 5x

•  $\frac{2}{y}=x$  

The speed r of a moving object is inversely proportional to the time t travelled is written as

• r=kt

• r= $\frac{k}{t}$

• t=kr

• $\frac{r}{k}=t$

A car travels a distance of d km in t hours. The formula that relates d to t is d=kt. What kind of variation is it?

• Direct

• Inverse

• Joint

• Combined

a varies inversely as b and a=10 when b = 2. Find the constant variation.

• 5

• 8

• 12

• 20

What happened to T when h is doubled in the equation T=4h?

• T is halved

• T is tripled

• T is doubled

• T becomes zero

What mathematical statement describes the graph

• yx=24

• y = 24x

• $y=\frac{24}{x}$

• $y=\frac{x}{24}$

If g varies jointly as h and i. If g = 24 when h = 3 and i = 2, find g when h = 5 and i = 3

• 4

• 24

• 30

• 60

If 3 men can do a portion of a job in 8days, how many men can do the same job in 6 days?

• 7

• 6

• 5

• 4

If r varies directly as s and inversely as the square or u, and r = 9 when s = 12 and u =2. Find r when s = 21 and u = 3.

• 3

• 5

• 7

• 9

Clark's income varies directly as the number of days that he works. If he earns P8,000 in 20 days. How much will he earn if she works in 40 days?

• P 12,000

• P16, 000

• P 20,000

• P 24, 000