NECO Mathematics Past Questions & Answers - Page 36

176.

If the mean of 3, 5, 8, k, 14 and 17 is 11, what is the value of k

A.

58

B.

38

C.

19

D.

11

E.

967

Correct answer is C

To calculate Mean: add up all the numbers ⇒ 3+5+8+k+14+17 = 47 + k then divide by how many numbers there are ⇒ 6 The Mean is already given as 11 11 = (47 + k) / 6 Cross multiply to solve for k : k = (6 X 11) - 47 k = 19

177.

The bearing of a point Y from point x is 150°. What is the bearing of X from Y?

A.

330°

B.

240°

C.

150°

D.

120°

E.

30°

Correct answer is A

No explanation has been provided for this answer.

178.

Simplify 27\(^{-\frac{1}{3}}\) \(\times\) 64\(^{-\frac{1}{3}}\) \(\times\) 4\(^{\frac{1}{3}}\)

A.

48

B.

12

C.

\(\frac{4}{3}\)

D.

\(\frac{1}{12}\)

E.

\(\frac{1}{48}\)

Correct answer is D

No explanation has been provided for this answer.

179.

Find the 19th term of the A.P. \(\frac{5}{6}\), \(\frac{8}{6}\), \(\frac{11}{6}\).................

A.

7\(\frac{1}{2}\)

B.

9

C.

9\(\frac{1}{2}\)

D.

9\(\frac{5}{6}\)

E.

10

Correct answer is D

first term (a) = \(\frac{5}{6}\)

common difference =   \(\frac{8}{6}\) - \(\frac{5}{6}\) → \(\frac{3}{6}\) or \(\frac{1}{2}\)

A.P formula → T\(_n\) = a + (n - 1)d
T\(_n\) = \(\frac{5}{6}\) + (19 - 1)\(\frac{1}{2}\)
T\(_n\) = \(\frac{5}{6}\) + 9

→ 9\(\frac{5}{6}\)

180.

Mr Aborowa bought a car for N200,000.00 and later sold it for N170,000.00. What is the percentage loss?

A.

11.60%

B.

7.60%

C.

15%

D.

17.65%

Correct answer is C

Using these:

Loss = C.p - S.p

: Percentage Loss = ( Loss X 100) ÷ C.p

=15 %