Answer: 20 oz of juice concentrate and 60 oz of water.
Explanation:
Translate the word statements into algebraic expressions to set a system of equations that you can solve.
1) Name the variables:
- j: parts of juice concentrate
- w: parts of water
2) Statement one, 2 parts juice concentrate to 6 parts water, translates into a proportion:
j / w = 2 / 6
3) Statement two, 80 oz of the drink, tanslates into an equality:
j + w = 80
4) Solve the system to find how many oz of juice concentrate and water Elena needs:
a) System:
j / w = 2 / 6
j + w = 80
b) Solve for w in the first equation: w = 6j / 2 = 3j
c) Substitute w in the second equation: j + 3j = 80
d) Combine like terms: 4j = 80
e) Use division property of equality: j = 20
f) Substitue in w = 3j: 3 = 3(20) = 60.
5) Solution: j = 20, w = 60.
6) Verify:
- j / w = 20 / 60 = 2 / 6 ⇒ right
- j + w = 20 + 60 = 80 ⇒ right
