Question

Ralph is 3 times as old as Sara. In 4 years, Ralph will be only twice as old as Sara will be then. Find Ralph's age now. If x represents Sarah's age now, which of the following expressions represents Ralph's age in four years?

Answer 1

R(c) = Ralph's current age
R(c)= 3x [given]
Answer:
R(c)=2x + 4
The 2 represents how much older Ralph is than Sarah, then the plus 4 equals the amount of years that has gone by since Sarah's original age.

Answer 2

Answer:

Sara present is 4 years and Ralph present age is 3x = 12

Step-by-step explanation:

Since, x represents Sarah's present age  then

According to question

Ralph is 3 times as old as Sara.

that is present age of Ralph = 3x

After 4 years age of Sara will be x + 4

and age of Ralph will be 3x + 4.

According to question,

In 4 years, Ralph will be only twice as old as Sara will be then.

⇒ 3x + 4 = 2( x + 4)

Solving for x, we get,

⇒ 3x + 4 = 2 x + 8

⇒ 3x -2x = 8 - 4

⇒ x = 4.

Thus, Sara present is 4 years and Ralph present age is 3x = 12