1). On a Friday night 18 pupils were in detention from a school of 800 pupils. What percentage of the school were in detention that Friday night?
2). 360 buses run from a depot, but 72 are being repaired.
What percentage of the total are in service ?
3). One day 132 trains arrive at a railway station and 99 are on time. What percentage of them
are late ?
4). In an exam a pupil gets 54 out of 72 marks. What percentage of the exam does he get wrong?
5). A dentist looks at Jean's 32 teeth, 12 of them have fillings.
What percentage don't have fillings?
6).
Billy has 250 school meals in a year. He has chips for 195 meals.
What percentage of school meals does Billy not have chips?

1. 18/800×100%

=2.25%

2. 288/360×100%

=80%

3. 33/132×100%

=25%

4. 18/72×100%

=25%

5. 20/32×100%

=62.5%

6. 55/250×100%

=22%

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2

step-by-step explanation:

1. practice, practice & more practice

2. review errors

3. master the key concepts

do not try to memorise the processes.

4. understand your doubts.

5. create a distraction free study environment

6. create a mathematical dictionary

7. apply maths to real world problems.