Answer:
Sister = 15 years old
Brother = 12 years old
Step-by-step explanation:
Right now, if the brother is B years old and the sister is S years old, B = (4/5)S because the ratio from brother to sister is 4:5, so if one unit is X, B = 4X and S = 5X
Three years ago, the brother was B-3 years old and the sister was S-3 years old. Keeping one unit as X, we have
B = 3X
S = 4X
B-3 = (3/4)(S-3)
Therefore, we have a system of equations
B = (4/5)S
B-3 = (3/4)(S-3)
Substitute (4/5)S for B into the second equation to only have one variable
(4/5)S - 3 = (3/4)(S-3)
(4/5)S - 3 = (3/4)S - 9/4
add 3 to both sides and subtract (3/4)S from both sides to isolate the variable and its coefficient
(1/20)S = 3/4
multiply both sides by 20 to isolate the S
S = 15
B = (4/5)S = 12
Answer:
If 0.2 = 20%, The probability that 1 person will be infected is 100%, according to theory.
(f∘g)(x) = f(g(x)) = f(x +2)
= 2(x +2) -1
= 2x +3 . . . . . selection D
Answer:
The <u>larger </u>size container and the Cold farms is the better deal for Sheldon.
Step-by-step explanation:
Given:
1 gallon = 8 pints

Multiply the gallons to 20
8 × 20 = 160
Then, the large size is 18.
4.50 ×4 =18 (1 Gallon= 4 quartz)
Therefore, the <u>larger </u>size container and the Cold farms is the better deal for Sheldon.
If Ramon needs the same amount of x as someone else find the missing part in the problem then the amount Ramon need (x) is you answer.