Primary 6 math question
I am not sure which concept to apply here. Appreciate your pointers. Thanks.
Question:
I have some red and yellow marbles in a bottle.
If i add in 20 red marbles, 60% of my marbles are yellow.
If I add in another 60 yellow marbles, 75% of my marbles are yellow.
How many marbles do i have in the bottle?
Zach's Answer: