Seven years back, a father was 48 years older than his son. At present the father is 4 times as old as the son. How old will the son be three years from now?
Choose the correct choice from the following answers:	A) 16 years	B) 17 years	C) 18 years	D) 19 years	E) 20 years
Using linear equations to convert the word problem:   ** F = fathers current ageS = sons current age   #1 Seven years back, a father was 48 years older than his son: F-7 = 48 + (S - 7)   #2 At present the father is 4 times as old as the son: F = 4*S   How old will the son be three years from now?: S + 3 = ?   With two variables and two linear equations we are able to solve the problem:   (S*4) - 7 = 48 +S -7   3S=48   S = 16   S + 3 = 16 + 3= 
<gadget id="calculator">16 + 3</gadget>
<output>19</output>
19   Answer: 19 years
<result>D</result>
Seven years back, a father was 48 years older than his son. At present the father is 4 times as old as the son. How old will the son be three years from now?