How old was ricin 1980?

Question

In the year 1980 ric was twice as old as Nancy who was twice as old as Michael. In the year 1993 ric. Nancy and michaels ages added up to 78 years. How old was rich in 1980

Answer 1

The easiest way to solve this question is to create some equations that will help simplify the problem; these equations can then be used to solve the problem. To start keep the equations in terms of the desired outcome/answer (in this case Rich's age), I will be assigning variables as follows:

R= Rich's age, N=Nancy's age, M= Michael's age

In 1980 the following is true:

R=2*N and because N=2*M we can combine those two equations for the variable we are solving for as follows

R=2*(2*M)= 4M

now we know that, in 1980, R=2N=4M

In 1993

The additional information from 1993 (13 years later) must be deconstructed to be useful. Subtract the total number of years aged, 13 years per person, from the 78 total years of age for 1993 to show that:

R+N+M=78-(13x3)=39 in the year 1980

so the total age in 1980 was 39

Now you have all of your necessary data for 1980, the year that we are calculating for. We know that in 1980:

R=2N=4M

and R+N+M=39

rearranging the first equation, we have N=1/2R and M=1/4R so R+(1/2R)+(1/4R)=39

solving for R you get (1 3/4)*R=39 so R= 22 years old in 1980