Answer:
• 3 weeks
,
• $207
Step-by-step explanation:
Part A
• Let the time it takes Hazel to finish 1 pound of tea = x weeks
,
• Jonathan alone uses up a pound of tea in six weeks.
,
• When they are both at home a pound of tea lasts two weeks.
This gives rise to the equation below:

First, we solve for x:

If Hazel were alone, a pound of tea would last 3 weeks.
Part B
There are a total of 52 weeks in a year.
• Hazel did not drink tea for 6 weeks
,
• Jonathan gave up drinking tea for six weeks.
The number of weeks for which they drank tea:

1 pound of tea last 2 weeks.
Therefore, the number of pounds they drank:

Since the tea costs $9.00 per pound, the amount spent:

The couple spends about $207 on tea during the year.