John had 100 dollars to buy drinks and sandwiches for his birthday party. He bought 5 small boxes of drinks at 4 dollars each box and 8 boxes of sandwiches at 6 dollars each box. How much money was left after the shopping?

Hint: Calculate the total amount of dollars spent at both the drinks and sandwiches and then subtract that amount from the total amount he carried with him.

Complete step-by-step answer:
John has 100 dollars for the shopping.
Firstly, he buys 5 small boxes of drinks at 4 dollars each.
So, he spent \[5 \times 4 = 20\] dollars at the drinks.
Now, he buys 8 boxes of sandwiches at 6 dollars each.
So, he spent \[8 \times 6 = 48\] dollars at the sandwiches.
The total amount of dollars he spent at both drinks and sandwiches is 20+48=68 dollars.
Now, for the amount of dollars left with him, we have to subtract the amount spent by him from the total amount he carried with him for the shopping purpose.
 \[\therefore 100 - 68 = 32\]
Thus, 32 dollars are left with him after the shopping.

Note: Alternate Method:
John has 100 dollars for the shopping.
Firstly, he buys 5 small boxes of drinks at 4 dollars each.
So, he spent \[5 \times 4 = 20\] dollars at the drinks.
Now, he is left with \[100 - 20 = 80\] dollars.
Then, he buys 8 boxes of sandwiches at 6 dollars each from the remaining 80 dollars.
So, he spent \[8 \times 6 = 48\] dollars at the sandwiches.
Now, he is left with \[80 - 48 = 32\] dollars.