A candidate scores 20% and fails by 50 marks, while another candidate who score 40% marks, gests 30 marks more than the minimun required marks to pass the examination. Find the maximum marks for the examination.

Let maximum marks be N.

According to the question,
40N/100 = 40 + 40
? 40N/100 = 80
? N = 200

Let original price be ? 100
Then, reduced price = ? 94
? Increase in consumption
= [(100 - 94)/94] x 100 %
= (6/94) x 100 %
= 6¹⁸/₄₇%

Let original price be ? 100
Then, increased price = ? 125

? Reduction in consumption
= [(125 - 100)/125 ] x 100%
= (25/125) x 100 %
= 20%

Given that, a = 20% and b = 5%

According to the formula
Required percentage = [20 - 5 - {20 x (5/100)}% = 14%

Net effect = [- 12 - 4 + {(-12) (-4)/100}]%
= (-16 + 0.48)%
= -15.52%

Given, R = 15% and R₂ = 20%
Required population
= P(1 + R₁/100) (1 - R₂/100)
= 126800(1 + 15/100) (1- 20/100)
= 126800 (1 + 3/20 ) (1- 1/5)
= 126800 x (23/20) x (4/5) = 116656

Given that,
P = 705600, R = 5% and n = 2

According to the formula,
Population after n yr = p(1 + R/100)ⁿ

? Population after 2 yr.
= 705600 x (1+ 5/100)²
= 705600 x (105/100)²
= 705600 x (21/20 x 21/20) = 777924

Given that,
p = 1058400, R = 5% and n = 2
According the formula,
Population n yr ago = P/(1 + R/100) ⁿ
? Population 2yr ago = 1058400/(1+ 5/100)²
= 1058400 x 20/21 x 20/21 = 960000

Population after 2 yr
= P (1 + R/100)²
= 250000 (1 + 2/100)²
? 250000 x (51/50) x (51/50) = 260100
? Growth = 260100 - 250000 = 10100

Let the number of boys = B
and number of girls = G
Then, 10% of B = 1/4 of G
? B/10 = G/4
? B/G = 10/4 = 5/2
? B : G = 5 : 2