numbers and percentages

numbers and percentages principles

1. Make sure the numbers/percentages are central to the problem NOT a distractor

2. Identify if numbers are being discussed or percentages or both AND then determine they represent an overall total or a portion

3. look for what is missing (total vs portion etc) bc the question usually hinges on the missing part

4. note if any number/percentage is rising or falling

5. If a conclusion is present it is typically faulty and confuses percentages vs numbers

6. If a conclusion isn’t present then the numbers and percentages work together to find the correct answer

numbers and percentages misconceptions

1. increasing percentages automatically lead to increasing numbers

increasing percentages automatically lead to increasing numbers misconception

• overall size of the group could get smaller leading to an increasing percentages

• decreasing percentages automatically lead to decreasing numbers misconception

• increasing numbers automatically lead to increasing percentages misconception

• decreasing numbers automatically lead to decreasing percentages misconception

• large numbers automatically mean large percentages and small numbers automatically mean small percentages

• large percentages automatically mean large numbers and small percentages automatically mean small numbers

decreasing percentages automatically lead to decreasing numbers misconception

• overall size of the group could get bigger leading to an decreasing percentages

increasing numbers automatically lead to increasing percentages misconception

• total number is also rising so percentage could still be proportional

decreasing numbers automatically lead to decreasing percentages misconception

• total number is also decreasing so percentage could still be proportional

large numbers automatically mean large percentages and small numbers automatically mean small percentages

• large number does not equal large percentages

large percentages automatically mean large numbers and small percentages automatically mean small numbers

• small percentages does not equal small numbers

amount

qountity

sum

total

count

tally

words introducing numerical ideas

percent

proportion

fraction

ratio

incidence

likelihood

probability

segment

share

words that introduce percentage ideas

numbers/probability general rules

• if the stimulus contains percentages or proportion information only avoid answers that contain hard numbers

• if the stimulus contains only numerical information avoid answers that contain percentage or proportion information

• if the stimulus contains both percentage and numerical information any answer choice that contains numbers/percentages or both may be true