Set, Algebra, business maths

There are 140 Learners in primary 8 sitting some examination, if not all, of the following examinations:

English, Maths and Science.

15 pupils are sitting both English and Maths but not Science

20 pupils are sitting Science and Maths but not English

18 pupils are sitting Science and English but not Maths

8 pupils are sitting all three exams

65 are sitting Science in total

55 are sitting English in total

72 are sitting Maths in total.

how many pupils did not sit any of these examinations.

Answer explanation

You can see each circle only has one section missing. Since we know the total number that took each subject, we can work out those missing sections.

Science

20 + 18 + 8 = 46

65 are sitting Science altogether

65 – 46 = 19

19 pupils are sitting Science only

Maths

20 + 15 + 8 = 43

72 are sitting Maths

72 – 43 = 29

29 pupils sitting Maths only

English

18 + 15 + 8 = 41

55 of the pupils are sitting English

55 – 41 = 14

14 pupils are sitting English

only We can now fill in this information on our diagram. Let’s add the values we have so far:

14 + 15 + 18 + 19 + 20 + 8 + 29 = 123

Now subtract this from the total number of pupils in Primary 8. 140 – 123 = 17 students failed to take exams

A salesperson is paid a commission on the value of goods sold. In one month she sold 600 items each at SSP1 500. If she was paid a commission at the rate of 5%, how much commission in South Sudanese Pounds did she earn?

Solomon paid SSP8 500 for a radio after getting a discount of SSP95. How much less would he have paid had he been given a discount of SSP115?

Gabriel bought a laptop on hire purchase terms. He paid a deposit of SSP 20 000. The remaining amount was paid in 8 equal monthly installments. He paid a total of SSP27680. How much was each monthly installment?

Philip bought a TV set on hire purchase items. She paid a deposit of SSP120 000 and 12 equal monthly installments of SSP 850 each. The hire purchase price was 20% more than the cash price. Sylvia bought the same TV set on cash. How much more did Alai pay for the TV set?

Worija bought a radio for SSP 720. He later sold it at SSP 630. What loss did Worija make?

Jacinta bought 15 bags of fruits at SSP 450 per bag. She spent SSP 500 on transport, 3/2 bags of the fruits got spoilt and she sold the rest at SSP 400 per bag. What was her loss?

find the intersection and union of the Venn diagram.

• intersection = {3, 7, 9, 20}

  union = {3, 7, 9, 10, 14, 15, 19, 20, 23, 24, 25, 26, 30}

• intersection = {3, 7, 9, 20}

  union = {3, 7, 9, 10, 11, 15, 19, 20, 23, 24, 25, 26, 30}

• intersection = {3, 7, 11, 20}

  union = {3, 7, 9, 10, 14, 15, 19, 20, 23, 24, 25, 26, 30}

list the set of A = The set of all even numbers less than 12

• {2, 4, 6, 0, 10}

• {2, 4, 6, 8, 10}

• {2, 4, 5, 8, 10}

list elements of J = {x : x = 5n - 3,n ∈ W, and n < 3}

• {-5, 2, 7}

• {0, 2, 7}

• {-3, 2, 7}