Answer:Neil is not correct
Explanation:
Let us calculate the total cost of the of the apps and headphone without estimation.
He wants to buy 5 apps priced at $0.99 each
Total cost of the 5 apps will be
5 × 0.99 = $4.95
He also wants to buy headphones priced at $15.49.
Since this includes shipping and tax. The total cost the 5 apps and headphone is 4.95 + 15.49 = $20.44
Neil only has a $20 gift certificate for an online store. This is actually lesser than the total cost of the items.
So Neil is wrong
Even if he estimated by rounding up, the most reasonable estimate would be
$1 per app and the 5 apps will cost $5
The headphone will be $15.5
The total would be 5+ 15.5 = $20.5.
This is still more than his gift certificate