# WAEC 2020 General Mathematics Essay & Obj Question And Answer

MATHS OBJ
*VERIFIED MATHS-OBJ*
1-10 CBCDACDCCD
31-40 CDACCCCCDA
41-50 BBBCDCACDB

==Completed==

IF YOU NEED FULL OBJ,KINDLY COMMENTS ‘I NEED IT’ AT THE CONMENT BOX

2ai).

p = (rk/Q -ms)2/3
p3/2 = (rk/Q -ms)2/8 * 3/2b
p3/2 = rk/Q = ms
p3/2 + ms = rk/Q
q(p3/2 + ms ) = rk
Q =rk/p3/2 + ms

2aii)
Where :
r = 10, k = 4, s = 0.2
p = 3, m = 15

Q = 10 * 4/3^3/2 + (15 * 0.2)
Q = 40/5.2 + 3
Q = 40/8.2
Q = 4.88
[17/08, 10:30 AM] Martail Jr: 5a)
Using elimination method
2x: 2p-4q=4
3x: 4p+2q=9

Hence
4p-6q=8
9p+6 =27
Therefore
13p=35

Thus p=35/13

Substituting P=35/13 in equation (ii)

Hence
3p+2q=9……….. (ii)
3(35/13) + 2q= 9
=105/13+2q=9

Multiplying throughout by 13
~13~ *105/ ~13~ + ~13~*2q =13*9
Thus 105+26q=117

Collecting like terms
26q =117-105
26q=12
Q=12/26 or 6/13

(1a)
Given A={2,4,6,8,…}
B={3,6,9,12,…}
C={1,2,3,6}
U= {1,2,3,4,5,6,7,8,9,10}

A’ = {1,3,5,7,9}
B’ = {1,2,4,5,7,8,10}
C’ = {4,5,7,8,9,10}
A’nB’nC’ = {5, 7}

(1b)
Cost of each premiere ticket = \$18.50
At bulk purchase, cost of each = \$80.00/50 = \$16.00

Amount saved = \$18.50 – \$16.00
=\$2.50
============================≠
(5a)
Total income = 32+m+25+40+28+45
=170+m
PR(²)=m/170+m = 0.15/1
M=0.15(170+m)
M=25.5+0.15m
0.85m/0.85=25.5/0.85
M=30

(5b)
Total outcome = 170 + 30 = 200

(5c)
PR(even numbers) = 30+40+50/200
=115/200 = 23/40

(5a)
Total income = 32+m+25+40+28+45
=170+m
PR(²)=m/170+m = 0.15/1
M=0.15(170+m)
M=25.5+0.15m
0.85m/0.85=25.5/0.85
M=30

(5b)
Total outcome = 170 + 30 = 200

(5c)
PR(even numbers) = 30+40+50/200
=115/200 = 23/40

4a) Total Surface Area = 224πcm²

r:l = 2:5

r/l = 2/5

Cross multiply

2l/2 = 5r/2

L = 5r / 2

Total surface = πrl + πr²

= πr (l + r)

24π/π = πr (5r/2 + r )/ π

224 = 5r²/2 + r²/1

L.c.m = 2

448 = 5r² + 2r²

448 / 7= 7r²/7

r² = 64

r = √64 = 8cn

L = 5*8/2 = 20cm

4b)

Volume = 1/2πr²h

= 1/3 * 22/7 * 8 * 8 * 18.33

= 1228.98cm³

L² = h² + r ²

20² = h² + 8²

400 – 64 = h²

h² = 336

h = √ 336

h = 18.33cm

(8a)
Let Ms Maureen’s Income = Nx
1/4x = shopping mall
1/3x = at an open market

Hence shopping mall and open market = 1/4x + 1/3x
= 3x + 4x/12 = 7/12x

Hence the remaining amount
= X-7/12x = 12x-7x/12 =5x/12

Then 2/5(5x/12) = mechanic workshop
= 2x/12 = x/6
Amount left = N225,000
Total expenses
= 7/12x + X/6 + 225000
= Nx

7x+2x+2,700,000/12 =Nx
9x + 2,700,000 = 12x
2,700,000 = 12x – 9x
2,700,000/3 = 3x/3
X = N900,000

(ii) Amount spent on open market = 1/3X
= 1/3 × 900,000
= N300,000

(8b)
T3 = a + 2d = 4m – 2n
T9 = a + 8d = 2m – 8n
-6d = 4m – 2m – 2n + 8n
-6d = 2m + 6n
-6d/-6 = 2m+6n/-6
d = -m/3 – n
d = -1/3m – n

(3a)
Diagram
CBD = CDB (base angles an scales D)
BCD+CBD+CDB=180° (Sum of < in a D) 2CDB+BCD=180° 2CDB+108°=180° 2CDB=180°-108°=72° CDB=72/2=36° BDE=90°(Angle in semi circle) CDE=CDB+BDE =36°+90 =126 (3b) (Cosx)² - Sinx given (Sinx)² + Cosx Using Pythagoras theory thrid side of triangle y²= 1²+√3 y²= 1+ 3=4 y=√4=2 (Cosx)² - sinx/(sinx)² + cosx (1/2)² - √3/2/ (√3/2)² + 1/2 = 1/4 - √3/2 = 1-2√3/4 3/4+1/2 = 3+2/4 =1-2√3/4 * 4/5 =1-2√3/5 (9a) Draw the triangle (9b) (i)Using cosine formulae q² = x² + y² - 2xycosQ q² = 9² + 5² - 2×9×5cos90° q² = 81 + 25 - 90 × 0 q² = 106 q = square root 106 q = 10.30 = 10km/h Distance = 10 × 2 = 20km (ii) Using sine formula y/sin Y = q/sin Q 5/sin Y = 10.30/sin 90° Sin Y = 5 × sin90°/10.30 Sin Y = 5 × 1/10.30 Sin Y = 0.4854 Y = sin‐¹(0.4854), Y = 29.04 INVITE YOUR FRIENDS AND FAMILY HERE

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