I’m thinking re the latest vid of @mindyourdecisions
No need to view his vid. Here’s the problem –
Brian has some boxes of paper clips. Some boxes hold 10 clips and some boxes hold 100. He has some paper clips left over. He has 3 more boxes with 100 paper clips than he has boxes with 10 paper clips. He has 2 fewer paper clips left over than he has numbers of boxes with 100 paper clips. What number of paper clips could he have?
- let x1 be the number of boxes with 10 clips
- x2 be the number of boxes with 100 clips
- n be the number of leftover clips
I thought of 100x2 = 10x1 + 300
Is that equation right? Something tells me I shouldn’t equate 100x2 to 10x1 plus 300. Something tells me I shouldn’t make an equation re number of clips as it isn’t explicit in the problem. I’m confused.
You are getting close. You are getting so many answers because you introduced the variable n. This makes it 2 equations and 3 unknowns. You need to cast the 2nd equation in terms of the number of boxes and the number of paper clips in each box rather than an additional variable. Here’s a hint. If:
x1 * 100 = 300 then x1=3
I.e. the total number of paperclips from the 100 paperclip boxes is 300 if there are 3 boxes of them