A chef got nine bags of onions. The red onions came in bags of 9 and the yellow onions Kaman bags of 10. If the chef got a total of 86 onions, how many bags of each type of onion did he get?

First you have to think about what to multiply 9 by to get a number that ends with 6. The answer to that is 3. So 9*3=36. Then you need to subtract 36 from 86. You get 50. So now you need to divide. 36/9=3 and 50/10=5. So the chef bought 3 bags of red onions and 5 bags of yellow onions.