The ideal weight of a nickel is 0.176 ounce. to check that there are 40 nickels in a roll, a bank weighs the roll and allows for an error of 0.015 ounce in total weight

 Total weight will be 7.055 ounces.

Step-by-step explanation:

Since we have given that

Ideal weight of a nickel = 0.176 ounce

Number of nickels in a roll = 40

Total weight becomes

Error that was allowed in total weight = 0.015 ounce

So, Total weight will be

Hence, Total weight will be 7.055 ounces.

answer: 7 x 2/5 = 2.8 hours, is your answer. your welcome! : 3

step-by-step explanation: first work out how long it took to hose 1/7 of the lawn which is 2/5 hours. times that by 7 to get the whole lawn.

sorry i don't know the other answer. i didn't learn what a proportional relationship is.