Answer:
Step-by-step explanation:
The ratios are all 3 father steps to 5 son steps. Then ...
son-steps = 5/3·father steps
son-steps = 5/3·36 = 60
and
father-steps = 3/5·son-steps
father-steps = 3/5·30 = 18
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As a check, you can realize that the numbers in the first blank, 36:60, are double those in the second blank, 18:30. The first of these, 36:60, is 3 times the row underneath it, 12:20.
