Answer:
Angela's age = 16 years
Harriett's age = 35 years
Step-by-step explanation:
Let Angela's age be x
Harriett's age = 2x + 3
x + 2x +3 = 51
3x = 51 -3
3x = 48
x =48/3
x = 16
Angela's age = 16 years
Harriett's age = 35 years
Answer:75
Step-by-step explanation:
40 represents a total, but then 45% represents a part. First of all, let's find the amount of girls in the club.
45% of 40
= 18 girls
If it was increased to 56%:
56% of 40
= estimated 23, since we can't have two fifths of a person.
23 - 18 = 5 new girls joined.
x = liters of 40% solution
y = liters of 70% solution
Gabe needs 30 liters, so
x + y = 30
Each liter of 40% solution contributes 0.4x liter of acid; each liter of 70% solution contributes 0.7y liter of acid. Gabe needs a solution with concentration 60%, which from 30 liters amounts to a net volume of 0.6*30 = 18 liters of acid. So
0.4x + 0.7y = 18
Solve the system however you like. By substitution, we have
y = 30 - x
0.4x + 0.7(30 - x) = 18
0.4x + 21 - 0.7x = 18
3 = 0.3x
==> x = 10 ==> y = 20
Answer:
<h2>B. x + 4y = 7</h2>
Step-by-step explanation:
