Discussion Forum

Natalie's Buckets of Slime - DMS Discussion

 
 
Admin ZIML的相片
Natalie's Buckets of Slime - DMS Discussion
Admin ZIML發表於2017年 10月 19日(Thu) 10:12
 

From the week of October 9 to October 13 we chose Thursday's problem (that you can find here):

Natalie's Big Slime factory produces two kinds of slime: Glitter Slime and Boring Slime. Last month, they produced $2500$ buckets of slime in total. Each bucket of slime contains $5$ gallons of slime. If they produced $1000$ more gallons of Glitter Slime than Boring Slime, how many buckets of Boring Slime did they produce last month?

38% of the students who tried the problem got it right on their first attempt.

The problem tells us the total number of buckets produced, and also gives us a clue about the difference between the number of buckets produced between the two available kinds. Note that if you know the sum of two numbers and also their difference, we have $$\text{Small number} = \frac{\text{Sum}-\text{Difference}}{2}.$$ So, once a student identifies this key information in the problem, is almost ready to finish it.

This time we noticed a popular answer for the problem was $5750$, which is larger than the total number of buckets produced, so it could not be the answer we are looking for. What could have happened?

It seems that students who chose to answer $5750$ clearly understood the problem and solved it, however, they answered the question in "number of gallons" instead of "number of buckets", as this number is exactly $5$ times the correct answer.

What do you do to check your answers are correct?

Share your thoughts and questions below!