Answer:100-7x
Explanation:
If x people are coming, he will spend the following
Sandwiches =2.50 × x= 2.50x
Drinks = 1.50 × x= 1.50x
Gift bags =3 × x=3x
Money left
Sandwiches = 50-2.50x
Drinks =25-1.60x
Gift bags = 25-3x
Total money left = 50-2.50x+25-1.50x+25-3x
=50+25+25-2.50x-1.50x-3x
=100-7x