A percent increase measures an added amount against the amount you started with. The cue is a quantity given at two times followed by a question about how much it increased. Subtract to find the added amount, then use Desmos to compare it with the earlier amount. Dividing by the later amount measures a different comparison.
Hints
- Hint 1
An absolute increase counts the extra units, not the percent they represent. Subtract the January count from the February count. How many more units did the factory make?
- Hint 2
A percent increase compares the extra units with the original production, then scales that comparison to 100. Which month's production was the starting amount?
Step-by-step
Find the change, then compare it with January
Step 1Find the increase in units
The absolute increase is the number of extra units. Subtract January's count from February's: type in Desmos. It shows , so the factory made more units in February.
- Step 2
Use the starting amount as the base
A percent increase compares the extra units with where production started, then multiplies that share by : . Divide by the original amount, not the new amount. January's is the original; using February's would compare the increase with the ending amount.
- Step 3
Calculate the percent increase
Type on the next Desmos line. It shows , so the production increase from January to February was . Choice C.