Answer:
16) w = 4/15
18) r -16 = 25; Ronald is 41.
Explanation:
16) Multiply by the reciprocal of the coefficient of w:
(1/3)·3w = (1/3)·(4/5)
w = 4/15
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18) Ronald's age is unknown and what we're asked to find. Let r represent Ronald's age in years. Then Wendy's age, being 16 years less than Ronald's, can be represented two ways:
Wendy's age: r-16 . . . . . . 16 years younger than Ronald
Wendy's age: 25 . . . . . . .given
We can equate these two versions of Wendy's age to have a subtraction equation to find Ronald's age:
r - 16 = 25 . . . . . . . the equation
r = 41 . . . . . . . . . . . the solution; found by adding 16 to both sides