Set up two equations:
1st: P (for Price family) + J (for Jenkins family) = 45 hours
2nd: 20P + 35J = 1200 liters
Rewrite the first equation as P = 45 – J
Replace P in the second equation:
20(45-J) + 35J = 1200
Simplify:
900 -20J + 35J = 1200
900 +15J = 1200
Subtract 900 from both sides:
15J = 300
Divide both sides by 15:
J = 300/15
J = 20
Jenkins used theirs for 20 hours
Price used theirs for 45-20 = 25 hours.
Answer:
Step-by-step explanation:
From the graph, we can conclude that,
is less than 2 and not including as there is a hollow circle at the mark 2.
Also, is greater than or equal to 7 including 7 as there is a solid circle at the mark 7
So, the compound inequality will be 
Now, the option that simplifies to the above inequality is the required answer.
Let us check the first option.
Therefore, option 1 simplifies to the above compound inequality.
So, the correct answer is option 1.
Let X = science homework.
Then math homework would be 3x ( three times as long).
Now you have math plus science = 64 minutes:
x + 3x = 64
Combine like terms:
4x = 64
Divide both sides by 4:
x = 64 / 4
x = 16
He spent 16 minutes on science and 48 minutes on math.
