NECO 2020 Mathematics Objective (OBJ) Answers to questions for 2020
The NECO Mathematics OBJ questions are those set of questions that are usually accompanied by 4 or 5 different options like (A, B, C, D, or E), and each of these questions has just one correct option. They are called multiple-choice questions.
10. Find the area of the curved surface of the cone if the cone is made from a sector of a circle that has a radius of 14cm and an angle of 90. (x = 22/7)?
Solution Solving: Length of arc = θ/360 * 2πr => r = 90/360 * 14/4 = 3.5 slant height t = 14cm curved surface area of cone = πrl => 3.142 x 3.5 x 14 = 153.95
Therefore, the answer is C
11. Find the size of the angle of the sector if a rope of length 18m is used to form a sector of a circle of radius 3.5m on a school playing field.
Correct your answer to the nearest degree.
Solution Solving: Circumference = 2πr
2 x 22/7 x 3.5 ≅ 22m, 22m = 360
11m = 360/22 x 11 = 1800
The correct answer is B.
12. Find Q ∩ P if P = (all odd numbers from 1 to 10) and Q = (all perfect squares less than 30)?
(1, 4, 9, 16, 25)
(1, 3, 4, 5, 7, 9, 16, 25)
(1, 3, 5, 7, 9)
Solution Solving: The only numbers that intersect between all odd numbers from 1 to 10 and all perfect squares that are less than 30 are [1 & 9]
Therefore, the answer = A
Sample NECO Mathematics Theory Questions 2020 (Paper 2)
Below are the sample NECO Mathematics theory questions 2020. They are essay questions gotten from last year’s exam. Study them effectively because they might be repeated in this year’s NECO Mathematics exam.
1. Evaluate log927
Solution; let’s assume x = log927
Then 9x = 27
Therefore, (32)x = 33
32x = 33
Divide it through by the coefficient of 2x
i.e. 32x /3 = 33/3
= 2x = 3 (equating indices) and x =1½
2. Solve log50.04
Solution: Let r be = log50.04, then 5r = 0.04 = 1/25 = 5-2 (equating indices)
Hence r = -2 Ans.
3. Solve 2x2 + 9x =5.
Solving solution: 2x2 + 9x =5
2x2 + 9x -5 =0
(2x – 1) (x + 5) = 0
Either 2x – 1 = 0 or x + 5 = 0
Therefore 2x = 1 or x = -5 so, x = ½ or x = -5 Ans.
5. An item is marked ‘cost N7000 VAT inclusive’. If the rate of VAT is 5%, how much VAT does the Government receive?
Solution: The price tag means that a 5% VAT surcharge is included in the total price. Thus N7000 represents 105% of the actual cost of the item.
105% of the cost price =N7000
1% of the cost of the item = N7000/105
5% of the cost (i.e. the VAT) =N7000/105 X 5
=N333 1/3 Ans.
6. Use the chain rule to differentiate (3x + 8)6
Solution: Let y = (3x + 8)6 and t = 3x + 8 then,
y = t6, dt/dx =3 and dy/dt =6t5
By the chain rule, we have; dy/dx = dy/dt X dt/dx
= 6t5 X 3
= 6 (3x + 8)5 X 3
= 18 (3x + 8)5 Ans.
7. Find the equation of the tangent to the curve y = x2 – 4x + 3 at the point (3, 1).
Solution: y = x2 – 4x + 3
= dy/dx = 2x – 4, the gradient function.
If x = 3, the gradient of the curve at this point is 2 X 3 – 4 =2
Hence, the gradient of the tangent at x=3 is 2, i.e. the same as the gradient of the curve. The equation of the tangent is, y-1/x-3 = 2
→ y – 1 = 2(x-3)
→ y = 2x – 5 Ans.
2020 NECO Exam Scheme and Format for Mathematics.
The NECO Mathematics exam will be in two papers (paper 1 and paper 2).
PAPER 1: Consist of compulsory questions which would last for fifty (50) minutes and carry fifty (50) marks. Each question has multiple-choice options ranging from A to D or E and only one of the options is to be selected for each question.
PAPER 2: Paper 2 known as theory paper is a “show working paper”. Candidates are to answer the questions by solving them on the essay solving sheet. All solving steps are to be properly shown on the working sheet.
Check out the NECO 2020 Mathematics syllabus and area of concentration and make sure you cover all the topics listed there because they are the topics NECO will set Mathematics questions 2020 from.
Go to the exam hall early.
Use only HB pencil to shade your OBJ answers.
Show working in all the theory questions.
Go with your Math set.
Remember to fill in your details (Name, Exam/Center Number) before you start.
Do not cheat.
Pray before and after your exam.
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