The answer is 1 hour and 40 minutes.
To find this answer, you should set up a proportion, or two fractions that are equal to one another:
the number of necklaces/the time it takes to make them
The first fraction in the proportion will be 12/2 and the second one will be 10/x, with the goal being to identify x. Now, you should set them equal to one another:
12/2 = 10/x
In a proportion, the first step is to cross multiply:
12 times x = 10 times 2
12x = 20
The second step is to divide to get x by itself on one side of the equation:
12x/12 = 20/12
x = 1.67
To answer the question, the last thing you have to do is convert 1.67 to hours and minutes. The 1 directly correlates to 1 hour, but the decimal needs to be converted to minutes. To do so, you will set up another proportion:
67/100 = x/60
Once you cross multiply and divide, you will end up with 40.2. So, the overall answer is 1 hour and 40 minutes.
