Quiz-1

Explanation:

Let the number of students be x.
Then, Number of students above 8 years of age = (100 - 20)% of x = 80% of x.
80% of x = 48 + 2/3 of 48
80/100x = 80
x = 100.

Explanation:
11 1/9 % = 1/9
1/9 × 900 = 100

Explanation:

70/280 = 1/4

1/4 × 100

= 25 %

Explanation:
Excess of B\'s height over A\'s = [(40/(100 - 40)] x 100% = 66.66%

Explanation:

Let the original number be x.
Final number obtained = 110% of (90% of x) =(110/100 * 90/100 * x) = (99/100)x.
x-(99/100)x=10
=> x =1000

Explanation:

Sugar in original solution = (75 x 30) / 100 = 22.5 g
Let x g of sugar be mixed
According to the question
{(22.5 + p)/(75 + p)} x 100 = 70
2250 + 100p = 75 × 70 + 70p
2250 + 100p = 5250 + 70p
30p = 5250 – 2250= 3000
=> p = 3000/30 = 100g

Explanation:
It will be 1/2(1%) = 1/2(1/100) = 1/200 = 0.005

Explanation:
While calculation in terms of percentage we need to multiply by 100, so
2.09 * 100 = 209.

Explanation:

Reduced price => Rp/100y per kg
R = Rs 270 , p=10% ,y=5kg
{(270×10)/(100×5)} = Rs. 5.4
Original prices per kg= Rp/(100-p)y per kg
{(270 x 10)/ (100 – 10)5} = 2700/450 = Rs. 6
Difference will be = 6-5.4= Rs 0.6 = 60 paise