Come up with a question and reasoning that would justify [70] as the answer.
The question is: Oliver owns a laundry shop, and he charges $2 per kilo of laundry. Two days ago, his shop washed a total of 5 kilos of laundries. Yesterday, it washed five kilos of laundries more than the previous day. Today, it washed twice the number of kilos than yesterday.  How much did he earn for three days?
Reasoning: Yesterday, his shop washed 5 + 5 = 10 kilos of laundry. Today, it washed 2 x 10 = 20 kilos of laundry. Thus, Oliver's shop washed a total of 5 + 10 + 20 = 35 kilos of laundries for three days. Therefore, his shop earned 35 x $2 = $70 for three days.

Come up with a question and reasoning that would justify [18] as the answer.
The question is: Billy can spit a watermelon seed 30 inches. Madison can spit a watermelon seed 20% farther than Billy. Ryan can spit a watermelon seed 50% shorter than Madison. How far can Ryan spit a watermelon seed?
Reasoning: Madison can spit a seed 20% farther than Billy's 30 inches so that's .20 * 30 = 6 inches farther. Billy spits a seed 30 inches and Madison can spit 6 inches farther for a total of 30 + 6 = 36 inches. Ryan can spit a seed 50% shorter than Madison's 36 inches for a total of .50 * 36 = 18 inches.

Come up with a question and reasoning that would justify [20] as the answer.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
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The question is: Kate wants to buy a special pen as a gift for her friend. The pen costs $30, and Kate only has money for a third of that amount. How much more money does she need to buy the pen?
Reasoning: Currently, Kate has only 1 / 3 * 30 = $10. That means Kate needs 30 - 10 = $20 more to buy the pen.