Answer:
6.25 grams
Step-by-step explanation:
Since we need to find the number of half-lives in 26.3 years, we simply divide 26.3 yrs by 5.26 yrs which yields 5 half-lives. This means that in 26.3 yrs the 200 grams of cobalt-60 will undergo 5 half-lives.
To obtain the remaining amount we simplify the expression;
A = 200*(1-0.5)^(26.3/5.26)
= 200*(0.5)^(5)
= 6.25 grams.
Therefore, the amount of a 200 g sample of colbalt-60 that will remain after 26.3 years is 6.25 grams
Sandwiches are $5.25 Bowls are $3.50
4x+5y=38.50
3x+9y=47.25
Answer:
see explanation
Step-by-step explanation:
Given that z varies directly with y and x then the equation relating them is
z = kxy ← k is the constant of variation
To find k use the condition x = 6, y = 12 and z = 10
k =
=
=
=
, hence
z =
xy ← equation of variation
The constant rate of change is $1.75 :)
This is because when the x value equals 1 the y value equals 4.75. And when the x value equals 2 the y value equals 6.50, so the rate of change is between the 2 y values which is linear so it has a constant rate of change of $1.75.
20 + 12x = 56
12x = 56 - 20
12x = 36
x = 36/12
x = 3
Bethany's monthly gym fee is $ 20
Bethany also pays $ 3 for a towel fee each visit