Afather is 60 years old and his son is half his age. how old was the boy when his father was four times his age? 6 years old 7 years old 8 years old 9 years old 10 years old

The father is 60, and the son is half of 60, so the son is 30.

The difference in ages is 60 - 30 = 30.

The difference in ages is 30 years. That difference is always true, no matter how old they are.

When the father was 4 times the age of the son, the son was b years old and the father was 4b years old. The difference in ages is still 30, so that gives us our equation.

4b - b = 30

3b = 30

b = 10

10 years old

answer: the price of one pound cabbage = $ 0.8

the point (10,8) represents that the cost of 10 pounds cabbage is $ 8

step-by-step explanation:

since, here is a proportional relation between the number of pounds of cabbage (x) and the price in dollars (y).

therefore, we can write,

⇒ y = k x

where k is the constant of proportionality.

now, point (5,4) is in the line.

thus, it will satisfies the above equation of line.

⇒ 4 = 5 k

⇒ k = 0.8

thus, the equation of the line is,

y = 0.8 x

a) for x = 1,

y = 0.8

therefore, the cost of one pound of cabbage is 0.8 dollars.

b) in the below graph (10,8) represents that the cost of 10 pounds of cabbage is 8 dollars.

0.02

step-by-step explanation:

time of 9 192 631 770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom at 0 k (but other seconds are sometimes used in astronomy)