Lizzy: In a classroom, there are blue chairs, green chairs, and white chairs. There are 10 blue chairs. The green chairs are 3 times as many as the blue chairs, and there are 13 fewer white chairs than the green and blue chairs combined. How many chairs are there in a classroom?.
Me: Hmmm, let me think. I think this is the detailed solution:
There are 10 x 3 = 30 green chairs. The total number of blue and green chairs is 10 + 30 = 40. So, there are 40 - 13 = 27 white chairs. Therefore, there are 40 + 27 = 67 chairs in a classroom. Final answer: 67.