Dr. Gallo's waiting room has a total of 18 magazines, including 3 fashion magazines. There are 5 more cooking magazines than there are decorating magazines. How many decorating magazines are there? You can use cubes to act out the problem.
f=3
c=d+5
so,
f+c+d=18
3+(d+5)+d=18
2d+8=18
2d=10
d=5
5 decorating magazines
if you were using cubes, you'd start out with 3 cubes for the fashion.
Then gather cubes together for the others, with 5 extras for the cooking.
Start adding in cubes until you get a total of 18:
f d c
3 1 6
3 2 7
3 3 8
3 4 9
3 5 10 <---------!!
To solve this problem, we can use cubes to represent the different types of magazines. Let's assign one type of cube to represent fashion magazines, another type for cooking magazines, and another type for decorating magazines.
Since there are 3 fashion magazines, we can use 3 fashion magazine cubes. Now, let's add 5 cooking magazine cubes, as there are 5 more cooking magazines than decorating magazines. So far, we have a total of 8 cubes.
We know that the total number of magazines in the waiting room is 18. To find the number of decorating magazines, we need to subtract the number of fashion and cooking magazines from this total.
Since we have accounted for 8 cubes so far, we subtract this number from 18: 18 - 8 = 10.
Therefore, there are 10 decorating magazines in Dr. Gallo's waiting room.