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January 2022 Brain Puzzler Solution

Q: A snail is at the bottom of a 12-foot well. She climbs up 3 feet during the day, but slides back 2 feet each night. How many days will it take her to get out of the well?

A: 10 days
After 5 days, she is 5 feet from the bottom. After 6 days, she is 6 feet from the bottom. It will take her less than 12 days.
At the end of the 9th day, she will be 9 feet from the bottom so on the 10th day when she climbs up 3 feet, she will reach the top!

November 2020 Brain puzzler solution

This puzzler has many solutions and is part of the Open Middle collection of problems. These questions stretch student thinking as they offer multiple solutions and are not PhotoMathable.

Place a digit in each box to make a true statement.
You can use 1 to 9 but only one time each.
How many solutions can you find?
(please do not use a calculator)

It seems that there are 10 solutions:
3/15 = 0.2
7/35 = 0.2
9/45 = 0.2
6/15 = 0.4
6/12 = 0.5
7/14 = 0.5
8/16 = 0.5
9/18 = 0.5
9/15 = 0.6

Here were the hints:
How does choosing the digits for the denominator affect the decimal value?
How might choosing the digit for the decimal make finding the digits for the fraction easier?

Converting a Fraction to a Decimal