Percent in Data Literacy
EXPECTATION
LEARNING GOAL
EXAMPLE
D1.1 explain why percentages are used to represent the distribution of a variable for a population or sample in large sets of data, and provide examples
Today we are reviewing how to calculate percentage and examining why it commonly used in data literacy
When Shaquille examined the free throw results of his teammates, he discovered that 65% of the first attempts were successful and 82% of the second attempts were successful.
MINDS ON
When we hear news regarding surveys, elections, statistics, etc. it is often expressed as a percentage.
Which do you think ‘sounds better’?
90 out of 120 voters support the new bill.
75% of voters support the new bill.
5 min
CALCULATING PERCENT
A value expressed as a percent represents the numerator of a fraction with a denominator of 100.
75% = 75/100
When our sample size is not exactly 100, we can create an equivalent fraction
¾ = 75/100
OR
We can divide the numerator by the denominator and then multiply by 100
3 ÷ 4 = 0.75 → 0.75 x 100 = 75
5 min
ACTION!
Salim surveyed his friends at school hoping to determine which car brand is the most popular. Here are his results:
20 min
Brand | Tallies | Total | Fraction | Fraction /100 | % |
Porsche | IIIII II | | | | |
BMW | IIIII IIIII II | | | | |
Mercedes | IIIII | | | | |
Ford | III | | | | |
Chevrolet | IIIII III | | | | |
Ferrari | IIIII IIIII IIIII | | | | |
Total → | | | | | |
ACTION!
Salim surveyed his friends at school hoping to determine which car brand is the most popular. Here are his results:
20 min
Brand | Tallies | Total | Fraction | Fraction /100 | % |
Porsche | IIIII II | 7 | 7/50 | 14/100 | 14% |
BMW | IIIII IIIII II | 12 | 12/50 | 24/100 | 24% |
Mercedes | IIIII | 5 | 5/50 | 10/100 | 10% |
Ford | III | 3 | 3/50 | 6/100 | 6% |
Chevrolet | IIIII III | 8 | 8/50 | 16/100 | 32% |
Ferrari | IIIII IIIII IIIII | 15 | 15/50 | 30/100 | 30% |
Total → | 50 | 50 | 50/50 | 100/100 | 100% |
DISCUSSION/EXTENSION
20 min
How do we convert between fractions, decimals, and percentages?
Which numbers are easy to convert?
Which numbers are challenging?
Why do you think that we ‘choose’ to use percent more often than decimals and fractions when presenting our findings?
CONSOLIDATION
Complete the following table.
5 min
Fraction | Fraction /100 | Decimal | Percentage |
45/100 | 45/100 | 0.45 | 45% |
16/50 | | | |
5/25 | | | |
3/20 | | | |
8/10 | | | |
2/5 | | | |
¾ | | | |
½ | | | |
CONSOLIDATION
Complete the following table.
5 min
Fraction | Fraction /100 | Decimal | Percentage |
45/100 | 45/100 | 0.45 | 45% |
16/50 | 32/100 | 0.32 | 32% |
7/25 | 28/100 | 0.28 | 28% |
3/20 | 15/100 | 0.15 | 15% |
8/10 | 80/100 | .8 | 80% |
2/5 | 40/100 | 0.4 | 40% |
¾ | 75/100 | 0.75 | 75% |
½ | 50/100 | 0.5 | 50% |
PRACTICE
Favourite Colour | Frequency | Fraction | Fraction /100 | Percentage |
Red | IIIII IIIII IIIII I | | | |
Blue | IIIII III | | | |
Green | IIII | | | |
Orange | IIIII IIII | | | |
Yellow | IIIII IIIII III | | | |
Total | | | | |
PRACTICE
Favourite Colour | Frequency | Fraction | Fraction /100 | Percentage |
Red | IIIII IIIII IIIII I | 16/50 | 32/100 | 32% |
Blue | IIIII III | 8/50 | 16/100 | 16% |
Green | IIII | 4/50 | 8/100 | 8% |
Orange | IIIII IIII | 9/50 | 18/100 | 18% |
Yellow | IIIII IIIII III | 13/50 | 26/100 | 26% |
Total | 50 | 50/50 | 100/100 | 100% |
PRACTICE
Favourite Sport | Frequency | Fraction | Fraction /100 | Percentage |
Hockey | III | | | |
Golf | IIII | | | |
Basketball | IIIII | | | |
Volleyball | IIIII II | | | |
Martial Arts | IIIII I | | | |
Total | | | | |
PRACTICE
Favourite Sport | Frequency | Fraction | Fraction /100 | Percentage |
Hockey | III | 3/25 | 12/100 | 12% |
Golf | IIII | 4/25 | 16/100 | 16% |
Basketball | IIIII | 5/25 | 20/100 | 20% |
Volleyball | IIIII II | 7/25 | 28/100 | 28% |
Martial Arts | IIIII I | 6/25 | 24/100 | 24% |
Total | 25 | 25/25 | 100/100 | 100% |