Answer:$7.50
Step-by-step explanation: make 4 boxes on a paper and put two lines in each box and you see that it is 8 in the boxes all to heather so that equals $8.00 so you can’t put a dollar in each box because if you do it will equal twelve dollars and you have to make ten dollars so you put $0.50 in each box so in each box it will be $2.50 in each box so you have to add $2.50 for times so it equals $10.00 so I added it it does add up to ten dollars so to see how much 3 bottles of water count you have to add up $2.50 3 timer and it equal $7.50
3 bottles of water costs $ 7.50
The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.
According to the problem,
4 bottles of water costs $ 10
1 bottle of water costs $ (10 / 4) = $ 2.50
3 bottles of water costs $ (2.50 x 3) = $ 7.50
∴Cost of 3 bottles is $7.50
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