Answer:
CD=7
Step-by-step explanation:
BAC angle=CED angle (alternate angles are equal)
therfore;
CB=CD(equal angle opposite sides are equal)
R=rita's age
m=mother's age
g=grandmother's age
mother is 4 times as old as rita
m=4r
grandmother is 2 times as old as mother
g=2m
sum is 104
r+m+g=104
subsitute 4r for m and 2m for g
r+4r+2m=104
subsitute 4r for m
r+4r+2(4r)=104
r+4r+8r=104
13r=104
divide both sides by 13
r=8
4r=m=32
8r=2m=g=64
rita is 8
mother is 32
grandmother is 64
0.1111 if you want it as a decimal
So, 0.5^5 is 0.03125
multiply that by 125 and get your answer.
*3.90625* (4)
just saying, I got the 0.5^5 thing because 5 is the number of half-lives (x) and 0.5 is the rate of loss (or whatever its called).
If it were to gain, you would put 1.5
