A cereal bar is sold individually for $2.40 or in packs of 4 for $8 per pack. Roxie wants to buy exactly 38 cereal bars. what is the least amount of money that Roxie can spend on cereal bars?

You would buy 9 packs of 4 bars so you would have 36 bars then you would buy 2 individuals bars to get you to 38 the least you would spend is $76.80

If Roxie were to buy the cereal bars individually, it would be

38 x $2.40 = $91.20

If she were to buy them in packs, she would need to buy 9 packs along with 2 individual bars (because there are 4 in each pack, 4x9=36 and adding 2 more would make it 38)

9 x $8 = $72

2 x $2.40 = $4.80

$72 + $4.80 = $76.80

The least amount of money Roxie can spend is $76.80 by buying the cereal bars in packs.