Given that y varies jointly as x and z, and y = 13 when x = 5 andz=8, find the following:
a. y when x= 4 and z=10
b. x when y= 20 and z = 12
c. z when x=6 and y=15

Step-by-step explanation:

y=kxz

13=k x 5 x 8

13= 40k

K=13/40

a. y=13/40 x 4 x 10

y=13/40 x 40

y=13

b. 20=13/40 x x x 12

20=13/40 x 12x

20=156x

40

20 x 40=156x

800=156x

X=800

156

X=200

39

X=5 5/39

C. 15=13/40 x 6 x z

15=78z

40

15x40=78z

600=78z

Z=600

78

Z=100

3

Z=7 9/13

answer: the correct answer is -32

step-by-step explanation:

1,407.5 hours

step-by-step explanation:

we first convert all the time to hours and then sum them up.

there are 24 hours in 1 day, in 58 days, there are 24 x 58 = 1,392 hours.

there are 60 minutes in 1 hour, thus, 30 minutes will be equivalent to 30 / 60 = 0.5 hours.

therefore, the number of hours it will take mercury to complete a full rotation is 1,392 + 15 + 0.5 = 1,407.5 hours