Alexander is a nut lover. He loves all kinds of nuts, but especially walnuts. He thinks they are crunchy, tasty and good for his brain. One day, he decides to go to the store to buy some walnuts for his snack. He sees that the price per pound of the walnuts is $8, which is quite expensive, but he doesn't mind because he loves them so much. He also has a coupon for $1 off the final amount, which makes him happy. He grabs 2 pounds of walnuts and goes to the cashier.
The cashier scans the walnuts and tells Alexander the total amount. Alexander uses his coupon and pays the cashier. How much did he pay? Well, let's see. The original price for 2 pounds of walnuts is 2 times 8, which is 16. Then, he subtracts 1 from 16, which is 15. So, Alexander paid $15 for his walnuts. That's a lot of money for nuts, but Alexander thinks it's worth it.
Now, what if Alexander wanted to buy a different amount of walnuts? How can we find the cost for any amount of walnuts? We can use an expression that uses a variable to represent the unknown amount. Let's call it p, for pounds. The cost for p pounds of walnuts is 8 times p, minus 1. That's because we multiply the price per pound by the number of pounds, and then subtract the coupon amount. So, the expression is 8p - 1. For example, if Alexander wanted to buy 3 pounds of walnuts, the cost would be 8 times 3, minus 1, which is 23. If he wanted to buy half a pound of walnuts, the cost would be 8 times 0.5, minus 1, which is 3.
So, now you know how to find the cost of walnuts for Alexander or anyone else who loves nuts as much as he does. Just remember to use the expression 8p - 1 and plug in the value of p that you want. And don't forget to use your coupon!