HackerRank Percentages Quiz- 1

Let Hardik’s salary be x and Krunal’s salary be y. Then Samson’s salary = 36% of Hardik

= \frac{36}{100} \times x = 0.36x …..(i)

Also, Samson’s salary = 54% of Krunal = \frac{54}{100} \times y = 0.54y …..(ii)

From (i) and (ii), we get

0.36x = 0.54y

36x = 54y

⇒ 2x = 3y

⇒ x = \frac{3y}{2}

Hardik’s salary as the percentage of Krunal’s salary

=> \frac{3}{2} \times 100=150

Hence, Hardik’s salary is 150% of Krunal’s weight.

Let the number be 100

30% increase ⇒ 1.3 x 100 = 130

40% decrease ⇒ (1 - 0.4) x 130 = 0.6 x 130  = 78

Overall change = [\frac{100-78}{100)} x 100]% = 22% decrease

Profit percentage = \frac{Profit}{Revenue} \times 100

= \frac{1.20}{200} \times 100

= 0.6%

Let’s the monthly income of Warren Buffet be x

Expenditure on tuition fees and room rent = 0.3x + 0.15x  = 0.45x

Remaining amount = x - 0.45x = 0.55x

Food expenses is half of remaining = 0.5 of 0.45x = 0.225x

Total Expenditure = 0.45x + 0.225x = 0.675x

Remaining income = x - 0.675x  = 0.325x

Savings = 40% of remaining ⇒40% of 0.325x = 0.13x

Given that 0.13x = 3250

So x = 25000

Warren Buffet’s expenditure on medicine = 0.325x - 3250

= 0.325 x 25000 - 3250 = 4875

Given that Elon Musk  scored 142 marks and still he failed by 26 marks

So the minimum pass marks = 142 + 26  = 168

Given that minimum pass marks = 40% of the total mark

Let x be maximum marks

Then 40% of x = 168

Or 0.4x = 168

x = \frac{168}{0.4}

= 420

Let the total polled vote = x

Amit got 60% vote

So modi’s vote share must be 40%

So total votes for Modi = 40% of x = 0.4x

Given that Modi got 280 votes

0.4x = 280

x =  \frac{280}{0.4} = 700

He sells 40L of milk everyday, which contains 20% of water

So water = 20% of 40L = 0.2 x 40 = 8L

So,

40L = 32L milk + 8L water

He adds 8L more water

Now mixture is

48L = 32L milk + 16L water

percentage of milk in the new mixture =  \frac{32}{48} \times 100 = 66.67%

70% of Virat’s salary = 25% of Sachin’s salary

Dividing by 7

10% of Virat’s salary = \frac{25}{7} % of Sachin’s salary

Multiplying by 3

30% of Virat’s salary =  \frac{25}{7} \times 3% of Sachin’s salary

= 10.71%  of Sachin’s salary

Let the two ages be Y and Z, such that

15% of Y = 21% of Z

Let, 24% of Y =  p % of Z

1% of Y = \frac{21}{15}% of Z

24% of Y = \frac{21}{15} \times 24% of Z

24% of Y = 33.6% of Z

Expenditure = Price x Consumption

Let p and c be initial price and consumption

And p’ and c’ be final price and consumption

p’c’ = pc

p’ = 85% of p = 0.85p

So 0.85pc’ = pc

c’ =  \frac{c}{0.85}

Percentage Increase in consumption = \frac{c’ - c}{c} \times 100

= \frac{\frac{c}{0.85} - c}{c} \times 100

= \frac{1 - 0.85 }{0.85} \times 100

= \frac{0.15 }{0.85} \times 100

=17.64%