Statistics - JSS1 Mathematics Past Questions and Answers - page 2

Percentage of people who prefer option A 

= (Number of people who prefer option A / Total number of people) × 100 Percentage

=(750/1000)×100

=75%

Percentage of defective units 

= (Number of defective units / Total number of units produced) × 100 Percentage

=(300/5000)×100

=6%

First, find the total score for the initial 30 students: Total score for 30 students=30×80=2400

Next, find the total score for the 5 additional students: Total score for 5 students=5×85=425

Combine the total scores: Combined total score=2400+425=2825

Find the new average score for the entire class of 35 students: New average score=2825/35=80.71≈81

First, find the number of widgets that fail quality control: Number of defective widgets=5000×(10/100)=500

Subtract the number of defective widgets from the total number of widgets produced: Number of widgets that pass quality control=5000−500=4500