Johannes was able to sell $30 / $2 = 15 kilograms last Wednesday. He was able to sell $24 / $2 = 12 kilograms last Friday. And he was able to sell $42 / $2 = 21 kilograms today. Therefore, Johannes was able to sell is 15 + 12 + 21 = 48 kilograms of cabbage.
The answer: 48
Reverse engineering the question: Johannes owns a vegetable shop, he sells cabbage for $2 per kilogram. If Johannes was able to earn $30 last Wednesday, $24 last Friday, and $42 today, how many kilograms of cabbage was he able to sell?

Austin works a total of 2 + 1 + 3 = 6 hours a week. Since he is paid $5 per hour of work, he'll earn $5 * 6 = 30 in a week. To make $180, he'll have to work for $180 / $30 = 6 weeks.
The answer: 6
Reverse engineering the question: Austin receives $5 for every hour he helps his father build a deck in their backyard. He works for 2 hours on Mondays, an hour on Wednesdays, and 3 hours on Fridays. If Austin wants to buy a bicycle that costs $180, how many weeks does he have to work?

The amount of material that Jennie needs per quilts is 21 yards / 7 quilts = 3 yards per quilt. In order to make 12 quilts, Jennie will need 12 quilts * 3 yards = 36 yards.
The answer: 36
Reverse engineering the question: Jennie makes quilts. She can make 7 quilts with 21 yards of material. How many yards of material would be required to make 12 quilts?

The range of scores is the difference between the highest and the least score so 75 = 98 - least score. Then the least score = 98 - 75 = 23. Mark scored twice as much as the least score which is 2 * 23 = 46.
The answer: 46
Reverse engineering the question:
In a math test, Mark scored twice as much as the least score. If the highest score is 98 and the range of the scores is 75, what was Mark's score?