It took Andrea 5.4 hours to drive to her mothers house on Sunday morning. On her return trip it took her 6 hours. Her average speed on Monday was 3 mph slower than on Sunday. What was her average speed on Monday?

The average speed on Monday is 27mph

Step-by-step explanation:

Given

Let:

So:

---- average speed slower on Monday than Tuesday

Required

The average speed on Monday

Average speed is calculated as:

Make d the subject

On Sunday, we have:

On Monday, we have:

The distance traveled is constant;

So:

Make s1 the subject in:

So, we have:

Open bracket

Collect like terms

Solve for s_2

The average speed on Monday is 27mph

step-by-step explanation:

72 is the answer to this problem