Answer:
$4.18
Step-by-step explanation:
You take $3.80 and multiply by it .1 (turn 10% into a decimal by moving the decimal to the right two places).
This gives you .38
Then you add .38 to $3.80 which gives you $4.18.
Answer:
19 because it greater and im guessing
Answer:
49
Step-by-step explanation:
side 1 = |18-3|= 15
side 2 = |12-3| = 9
side 3 = |16-4| = 12
side 4: 
perimeter = 15 + 9 + 12 + 13,4= 49,4 = 49
One value: would be a single valued function, or just one answer.
Real numbers would be: natural numbers, whole numbers, integers, rational numbers (fractions and repeating or terminating decimals), and irrational numbers.
No solution: there is no answer to the question.
He needs it 4 inches longer because 4 ft is 48 inches.