Question

A bag contains yellow marbles and red marbles, 32 in total. The number of yellow marbles is 5 more than 2 times the number of red marbles. How many yellow marbles are there?

Answer 1

Let R=number of RED marbles, and Y=number YELLOW marbles.

There is a total of 32 marbles, or Y+R=32, => R=32-Y

"The number of yellow marbles is 5 more than 2 times the number of red marbles. " expressed in terms of R is then

Y = 5+ 2R

Substituting R=32-Y,

Y=5+2(32-Y)=5+32-y=54-2Y

Solve for Y

3Y=54

Y=54/3=18

There are 18 Yellow marbles.

Answer 2

There are 20 yellow marbles .
Because 20+12=32