Question

Sally and Karl work at different jobs. Sally earns $7 per hour and Karl earns $5 per hour. They each earn the same amount per week but Karl works 2 more hours. How many hours a week does Karl work ?

Answer 1

To find out how many hours Karl works, we use the equations 7S = 5K and K = S + 2. Solving these equations, we find out that Karl works 7 hours per week.

Step-by-step explanation:

To solve the problem of how many hours a week Karl works, we can set up an equation using the information given about Sally and Karl's hourly wages and the fact that Karl works 2 more hours per week.

Let's denote the number of hours Sally works as S and the number of hours Karl works as K. Since Karl works 2 more hours than Sally, we can express this as K = S + 2. According to the problem, Sally earns $7 per hour and Karl earns $5 per hour, but they earn the same amount per week. This gives us the equation 7S = 5K.

Next, we can substitute S for K - 2 in the equation, giving us 7(S) = 5(K) or 7(K - 2) = 5(K). This simplifies to 7K - 14 = 5K.

Now, we solve for K:

7K - 5K = 14

2K = 14

K = 7

Thus, Karl works 7 hours a week.

Answer 2

Karl works 7 hours a week

Step-by-step explanation:

Step 1: Determine total amount that Sally earns

Total amount Sally earns=rate per hour×number of hours worked(h)

where;

Rate per hour=$7 per hour

Number of hours worked=h

Replacing;

Total amount Sally earns=(7×h)=7 h

Step 2: Determine total amount Karl earns

Total amount Karl earns=rate per hour×number of hours worked

where;

rate per hour=$5

number of hours worked=2 more than Sally=h+2

replacing;

Total amount Karl earns=5(h+2)

Step 3: Equate Sally's total earnings to Karl's total earnings and solve for h

7 h=5(h+2)

7 h=5 h+10

7 h-5 h=10

2 h=10

h=10/2

h=5

Karl works (h+2) hours=(5+2)= 7 hours

Karl works 7 hours a week