2021 General Mathematics WAEC Objective OBJ Answer

2021 General Mathematics Objective

OBJ Answer 1-10 DBADACDABD 11-20 BBBDBADADD 21-30 ACDABDDCDB 31-40 CDABCCCACD 41-50 ADDBDDADAB Maths Essay answers. (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 (2ai) P = (rk/q – ms)⅔ P^3/2 = rk/q – ms rk/q = P^3/2 + ms Q= rk/p^3/2 + ms (2aii) When P =3, m=15, s=0.2, k=4 and r=10 Q = rk/p^3/2 + ms = 10(4)/(3)^3/2 + (15)(0.2) = 40/8.196 = 4.88(1dp) (2b) x + 2y/5 = x – 2y Divide both sides by y X/y + 2/5 = x/y – 2 Cross multiply 5(x/y) – 10 = x/y + 2 5(x/y) – x/y = 2 +104x/y=12x/y=3x:y=3:1(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 (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 = 8cm L = 5*8/2 = 20cm (4b) Volume = 1/2πr²h = 1/3 * 22/7 * 8 * 8 * 18.33 = 1228.98cm³ L² =h²+r²20²=h²+8²400–64=h² h² = 336 h = √ 336 h = 18.33cm (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 (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 (2ai) P = (rk/q – ms)⅔ P^3/2 = rk/q – ms rk/q = P^3/2 + ms Q= rk/p^3/2 + ms (2aii) When P =3, m=15, s=0.2, k=4 and r=10 Q = rk/p^3/2 + ms = 10(4)/(3)^3/2 + (15)(0.2) = 40/8.196 = 4.88(1dp) (2b) x + 2y/5 = x – 2y Divide both sides by y X/y + 2/5 = x/y – 2 Cross multiply 5(x/y) – 10 = x/y + 2 5(x/y) – x/y = 2 +104x/y=12x/y=3x:y=3:1(7a) Diagram Using Pythagoras theorem, l²=48² + 14² l²=2304 + 196 l²=2500 l=√2500 l=50m Area of Cone(curved) =πrl Area of hemisphere=2πr² Total area of structure =πrl + 2πr² =πr(l + 2r) =22/7 * 14 =22/7 * 14 * 78 =3432cm² ~3430cm² (3 S.F) (7b) let the percentage of Musa be x Let the percentage of sesay be y x + y=100 ——————-1 (x – 5)=2(y – 5) x – 5=2y – 10 x – 2y=-5 ——————-2 Equ (1) minus equ (2) y – (-2y)=100 – (-5) 3y=105 y=105/3 y=35 Sesay’s present age is 35years (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–2nt9=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 (9c) Speed = 20/4, average speed = 5km/h (12a) Bcd=abc=40°(alternate D) DDE=2*BCD( DDE = 2*40 = 80° OD3=OED(BASE < of I sealed D ODE) ODE + OED + DOE= 180°(sum of < is in D) 2ODE+DOE=180° 2ODE+80°=180 2ODE+180=180 2ODE+100° ODE+100/2=50° (12bi) Digram (12bii) Area of parallelogram = absin =5*7*sin125° =35*sin55° =35*0.8192 =28.67 =28.7cm²(1dp) (12c) Given x=1/2(1-√2) 2x²-2x=2²-2(1/2(1-√2)} =2-(1-√2) =(3-2√2/2)-(1-√2) =3-2√2-2+2√2/2=1/2 These are provided for study purposes only. Bookmark this page and keep refreshing for updates. Also subscribe to all our notifications.

integrating their reward boxes or other elements that are discordant with the new laws of chance. There are many European countries that have started to work to regulate this kind of content and keep vulnerable players away from possible elements that could be harmful. It is important to note that the video games that went on sale before the proclamation of the new rules will remain as they are and will not undergo any changes. It is only the new titles that have to be adapted. Hence, Pokémon is going to have to find a solution for those remakes that it has in mind. Neither does the Japanese company come as a surprise, since in its latest creations it has had to look for alternatives. For the Pokémon Let's Go edition it has already introduced changes , leaving behind the slot machines inside the casino and replacing them with arcade machines , while in the new editions of Diamond and Pearl that are still to be released it seems that the game room will be replaced by a clothing store . That could be the future of the new remakes, the total or partial replacement of the gambling buildings, since they do not seem willing to accept the new qualification. Therefore, that return that the casino had made in the most recent versions of Pokémon seems to be more fleeting than expected. It must be remembered that the purpose of the slot machines was none other than to bet game chips to try to win more and exchange them for the prizes that were available. The user decided the pay lines and the amount that he put into play hoping to have a stroke of luck. Something that in 1996 was seen as something normal, but that a posteriori has been criticized by various associations dedicated to the sector. With no date for these new remakes to appear officially, Pokémon is already warned of which is the way to go and what would be a cumbersome path that would complicate things. The loophole left by PEGI is that if gambling is included in narrative elements, this rule would not apply. But in the case of Pokémon, being a building within the platform itself, there would be no room for doubt. Imagining a child being deprived of getting his game because he is unfit for his age seems somewhat surreal to Pokémon. And everything indicates that it will not happen.

Cares, will probe the future of education, labour, skills, informal education and knowledge-based systems. Looking to 2022, Travel and Connectivity Week, in association with Emirates and Etisalat, will cover digital communication, digital government, smart transport, supply chains, trade and travel. The United Nations will co-host Global Goals Week, which will see an emphasis on women and social development. Health and Wellness Week will bring together participants, including the World Health Organisation and the Mohammed bin Rashid Medicine and Health Sciences University, to discuss healthcare systems, medical tech solutions, healthcare services for local communities, and wellness and happiness. Attention to these issues is especially important in a pandemic world. Food, Agriculture and Livelihoods Week will shed light on key topics including food systems, food waste, food safety, small agricultural projects and food security, held in association with Pepsico, the Minister of State’s Office for Food and Water Security and Ministry of Climate Change and Environment. The series will end with Water Week, co-curated with the Minister of State’s Office for Food and Water Security, Ministry of Energy and Industry, and Ministry of Climate Change and Environment. Topics will include water management, oceans and the ocean economy,water-basedenvironmental systems, water supply networks and sanitation.

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