Suggested answer:

Assuming money that:

Linda has 4 unit, (4/7 of remaining)

Maria has 3 unit (3/7 of remaining)

Joe has 14 unit ((4+3) x 2 unit)

Total 21 unit of money, if share equally, each will ha 7 unit.

For Maria,

3 unit + $80 – $8 = 7 unit

4 unit = $72

1 unit = $18

Amount Joe gave to Linda will be,

($18 x 7) – $80 = $46

a) Joe gave $46 to Linda.

$18 x 21 = $378

b) Total amount of money will be $378

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