The networking organization you joined is throwing a party. You are in charge of buying the chips, which cost $2.50 per bag and salsa, which costs $4 per jar. The chips & salsa budget you are given totals $60. The inequality 2.5x + 4y less than or equal to 60 represents the possible combinations of chips (x) and salsa (y) you can buy.

Question

anonymous · Answer

Which of the following does not represent a solution to the inequality?

 10 bags of chips and 2 jars of salsa
 20 bags of chips and 2 jars of salsa
 14 bags of chips and 5 jars of salsa
 18 bags of chips and 6 jars of salsa

I THINK ITS C BUT IM NOT SURE

anonymous · Answer

@Tommynaut

tommynaut · Answer

Why do you think it's C? Can you explain your working out?

anonymous · Answer

my friend told me its C! BUT she not sure, thats what i ask you

tommynaut · Answer

Can you please give the question a go? It's not too different to the last question you did and uses some similar techniques.

anonymous · Answer

ok

tommynaut · Answer

Ok so we have the equation
$$2.5x + 4y \le 60$$ where x is chips and y is salsa. I'd say this question is easier than the last one you did because you just have to substitute numbers in.

Try 10 bags of chips and 2 jars of salsa. That means x = 10 and y = 2, right?
So we have 2.5(10) + 4(2) = 33. 
33 is indeed less than 60, so it works.
But we're looking for which one doesn't work.

So try the same approach with the other chip/salsa combos.

anonymous · Answer

D?

tommynaut · Answer

Excellent.

anonymous · Answer

thank you!!1

tommynaut · Answer

To check your answer visually, you can look at the image. Look for where x = 18 and y = 6. See how it's only just outside the region?

No problem :)