SOLUTION: solve this: A is 3 times as old as B and B is 5 years older than C. If B is X years old write the algebraic expressions for following. a) A's age today b) C's age today c) A's

Question 880029: solve this: A is 3 times as old as B and B is 5 years older than C. If B is X years old write the algebraic expressions for following.
a) A's age today
b) C's age today
c) A's age in 6 years time
d) The sum of A and B age in 4 years time
Answer by Edwin McCravy(20056) (Show Source): You can put this solution on YOUR website!
solve this: A is 3 times as old as B and B is 5 years older than C. If B is X years old write the algebraic expressions for following.

1.  A is 3 times as old as B 
    A = 3B


2.  B is 5 years older than C. 
    B = C+5

3.  B is X 
    B = X

a) A's age today

From (1),  A = 3B
From (3),  B = X
Substituting X for B
           A = 3X

---------------------------

b) C's age today

From (2), B = C+5
From (3), B = X
Substitute X for B
          X = C+5
Subtract 5 from both sides
        X-5 = C

---------------------------

c) A's age in 6 years time

Since from a), A = 3X  
Add 6 to both sides:
             A+6 = 3X+6    

Answer: 3X+6

---------------------------

d) The sum of A and B age in 4 years time

A is 3X now, so in four years, A will be 3X+4
B is  X now  so in four years, B will be X+4

In four years their sum will be

                (3X+4)+(X+4) = 3X+4+X+4 = 4X+8

Answer: 4X+8

Edwin

RELATED QUESTIONS
A is twice as old as B, and C is 5 years younger than B. 3 years from now, A will be 3... (answered by Earlsdon)

A is 4 years older than b,who is 3 times as old as c.if the sum of their ages is 25 how... (answered by algae132)

A is 6 years older than B,who is 4 times as old as C. If the sum of their ages is 33,... (answered by Seutip)

I have no idea how to solve this, if I could I would be an accountant. And why is this... (answered by Alan3354)

Mary is 4 years older than John. Mr Smith is 5 times as old as John. If John is x years... (answered by stanbon)

A is 20 years older than B. He is also 6 times as old as B. find their... (answered by bucky)

Please help me solve this: "A is 2 years older than B. 5 years from now, A will be 16/15 (answered by rothauserc)

The ages of three brothers, A,B and C, add up to 22. A is 2.5 times older than C. When A... (answered by robertb)

A is three as old as B, C is half as old as D and 8 years older than B. In ten years the... (answered by htmentor)