Number of Peanut Butter & Jelly Sandwiches

Jack prepared the following types of sandwiches for 90 Boy Scouts going on the weekend Jamboree in the ratio of 2 to 5 to 8: Peanut butter and honey, peanut butter and banana, and peanut butter and jelly. Each boy will get only one sandwich. How many peanut butter and jelly sandwiches did Jack make?


A. 48
B. 17
C. 30
D. 52

Let me see.

Let s = sandwiches

Let 2 to 5 to 8 be 2s : 5s : 8s.

There are 90 Boy Scouts.

Let 2s be for the honey; 5s for banana and 8s for jelly.

2s + 5s + 8s = 90

15s = 90

s = 90/15

s = 6

I said 8s = number of peanut butter and jelly sandwiches.

So, 8(6) = 48.

I say the answer is choice A.

 

correct

 

Another miracle. Sometimes, I amaze myself.

 

What I would have done: Let x be the number of peanut butter and honey sandwiches. Then there are 5x/2 peanut butter and banana sandwiches and 8x/2= 4x peanut butter and jelly sandwiches.
They total x+ 5x/2+ 4x= 90. Multiply both sides by 2: 2x+ 5x+ 8x= 15x= 180 so x= 180/15= 60/5= 12.
There were 12 peanut butter and honey sandwiches, 5(12)/2= 5(6)= 30 peanut butter and banana sandwiches, and 4(12)= 48 peanut butter and jelly sandwiches.

That is, of course, essentially what you did.

 

Brother, please come down to Earth. No need for sarcasm. Math is just a hobby to me.

 

??? There was no sarcasm! I just showed a different way to do that problem.

 

Another way? Ok. Another way.

 

Your not wrong it's answer a

 

Yes, I know.