Linear Worded Eqaution

[Vladdy]

"Pablo’s father is 4 years older than his mother and Pablo is a third his mother’s age. Their combined age is 74 years", right now im at the beginning of this problem and i'm trying to figure out who i should put as X for my unknown and also what equation i should use to find one third if its x/3 or something else, any help would be great.

 

[skeeter]

f = m+4

p = m/3

f + p + m = 74

(m+4) + (m/3) + m = 74

solve for mom’s age, m , then determine father’s and pablo’s ages

 

[HallsofIvy]

I, like skeeter, would NOT "put X" for any unknown because there are three unknowns! I would, however, have stated explicitly, the "p stands for Pablo's age", "f stands for Pablo's father's age", and "m stands for Pablo's mother's age".

Now, "Pablo’s father is 4 years older than his mother" so f= m+4.
"Pablo is a third his mother’s age" so p= m/3.
"Their combined age is 74 years" so p+ m+ f= 74.

 

[Vladdy]

I, like skeeter, would NOT "put X" for any unknown because there are three unknowns! I would, however, have stated explicitly, the "p stands for Pablo's age", "f stands for Pablo's father's age", and "m stands for Pablo's mother's age".

Now, "Pablo’s father is 4 years older than his mother" so f= m+4.
"Pablo is a third his mother’s age" so p= m/3.
"Their combined age is 74 years" so p+ m+ f= 74.

Yes, makes sense im here trying to calculate each of their ages based off these now.

 

[Oiler]

"Pablo’s father is 4 years older than his mother and Pablo is a third his mother’s age. Their combined age is 74 years", right now im at the beginning of this problem and i'm trying to figure out who i should put as X for my unknown and also what equation i should use to find one third if its x/3 or something else, any help would be great.

when assigning variables for word problems, in general it does not matter very much which is labelled the unknown, and which are the unknowns in terms of that Unknown which was assigned a variable. the math usually turns out equivalent in difficulty, but when it doesn’t; thenyou at least receive an exercise in slightly more complicated( or easier if your lucky) equation rearranging.

In this particular case however, the question is already providing the other unknown ages in terms of the age of pablo’s mother so it is more natural to let the age of pablo’s mother be [MATH]x[/MATH]But note that If you do let[MATH]x[/MATH] represent the age of pablo’s mother, then upon forming and solving for x an equation of [MATH]100=F(x)[/MATH] you would have solved for the age of pablo’s mother before solving for the ages of her son and husband.
So if you were interested in a particular person’s age then it would be advisable to let that person’s unknown age be [MATH]x[/MATH] instead, even if it requires a little more thought to formulate the final equation