Answer: 2 and 17/20 mm is the total thickness of the stack.
Step-by-step explanation:
Get the values you need for the dime and the penny from the chart:
dime: 1 and 7/20mm , penny: 1 and 1/2mm
Find common denominators for the fractions given in the chart.
20 will work because 1/2 is the same as 10/20.
Add the numerators of the fractions: 7 + 10 = 17 so the fraction will be 17/20
Add the whole numbers 1 + 1 = 2
Put it all together and now you've got 2 and 17/20 mm
