5% income of A is equal to 15% income of B and 10% income of B is equal to 20% income of C. If income of C is Rs.2000, then total income of A, B and C is?

Surface area sphere = 4? x (10)²
volume sphere=4?/3 x (10)³
= (4000?/3) cm³

? Required percentage = {(400? x 3) / (4000?)} x 100 %
= 30%

Let original rate = Rs. P per kg
New rate = 79% of Rs. P per kg
= Rs. (79 x P)/100) per kg
? {(100/79P)/100} - {100/P} = 10.5
? 10000/79P - 100/P = 10.5
? 10000 - 7900 = 10.5 x 79P
? P = 2100/(10.5 x 79)
? P = 2100/(10.5 x 79)
Reduced rate = Rs. (79/100) x 2100/(10.5 x 79) per kg = Rs. 2 per kg.

Required number = 800 x (1 + 15/100)²
= 800 x (23/20) x (23/20)
= 1058

Consumption Decreases = (common %)²/100
= 225/100
= 2.25%.

Let length of a rectangle = 100 m,
Breadth = 100 m
New length = 160 m,
New breadth = B meters
Then, 160 x B = 100 x 100
? B = (100 x 100) / 160 = 125/2
Decrease in breadth = (100 - 125/2)% = 37¹/₂%

Total population = 300000
Total number of males = 180000
Total Literates = 50% of total population = 150000
Number of literate males = 70% of males = 126000
? Number of literate females = 150000 - 126000 = 24000

Let the original price be ? N per kg.
New price per kg = 60% of N = 3N/5
? 120 / (3N/5) - 120/N = 32
? 600/3N - 120/N = 32
? 200/N - 120/N = 32
? 80/N = 32
? N = 80/32 = 2.5
So, the original price is ? 2.50

Let the number be N.
Then, error = 5N/2 - 2N/5 = 21N/10
? Error percentage = (21N/10) x (2/5N) x 100 % = 84%

Marks secured by Anirudh = [(85/100) x 100] + [(70/100) x 120] + [(65/100) x 140] + [(60/100) x 160]
= (85 + 84 + 91 + 96) = 356
? Required percentage = [356/(100 + 120 + 140 + 160)] x 100 %
= (356/520) x 100% = 68⁶/₁₃%

Number of failures = 10% of 950 + 40% of 250
= (10/100) x 950 + (40/100) x 250 = (95 + 100) = 195
Fail percentage = [195/(950 + 250)] x 100
= (195/1200) x 100 = 16.25%