$ 3.50 per lb * 1 1/2 lbs
3.50 per lb * 1.5 lbs = 5.25
It will cost $5.25
Given:
The total cost of the order is

where, T is the total cost, b is the number of bath towels, and w is the number of wash cloths.
Her budget is $85.
To find:
The constraints, so that she can order a maximum of washcloths or bath towels.
Solution:
We have,

Her budget is $85. So, total cost is less than or equal to 85.
...(i)
For maximum number of bath towels, the number of wash cloths is 0.

Divide both sides by 6.
For maximum number of wash cloths, the number of bath towels is 0.


Divide both sides by 2.


Therefore, the required constraints for maximum of washcloths or bath towels are
and
respectively.
29.37 rounds to 29
109.96 rounds to 110
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The rule is that if the decimal portion is 0.50 or higher, then you round up. Otherwise you round down.
We use the law of the sum of the 3 first terms of the geometric sequence: