Water makes about 3/4 of a person’s weight. 1. if a student weighs 86 lbs., how much of his weight is water? 2. if a student weighs 70 lbs., how much of his weigh is water? 3. if water makes 30 lbs. of a student’s weigh, how much does this student weigh? 4. if water makes 45 lbs. of a student’s weigh, how much does this student weigh? 5. if water makes 60 lbs. of a student’s weigh, how much does this student weigh?

1.  64.5 lbs

2. 52.5 lbs

3. 40lbs

4. 60 lbs

5. 80 lbs

Step-by-step explanation:

To determine how much of a persons weight is water, multiply 3/4 by their weight.

1. weight of water =  weight * 3/4

                               = 86 * 3/4

                               = 64.5 lbs

2. weight of water =  weight * 3/4

                               = 70 * 3/4

                               = 52.5 lbs

3. weight of water =  weight * 3/4

                      30         = weight * 3/4

                       Multiply by 4/3 on each side

                    30*4/3 = weight *3/4*4/3

                  40 = weight

4. weight of water =  weight * 3/4

                      45         = weight * 3/4

                       Multiply by 4/3 on each side

                    45*4/3 = weight *3/4*4/3

                  60 = weight

5. weight of water =  weight * 3/4

                      60         = weight * 3/4

                       Multiply by 4/3 on each side

                    60*4/3 = weight *3/4*4/3

                  80 = weight