Ratio, proportion and averages

Ratios, proportions, averages and mixtures.

General Test7 questions

Key ideas

Divide an amount in ratio a : b: the shares are a/(a + b) and b/(a + b) of the total.
In a proportion a : b = c : d, a × d = b × c.
Average = sum of observations ÷ number of observations.

₹720 is divided between A and B in the ratio 5 : 7. What is B’s share?	Easy
What is the average of the first 10 natural numbers?	Easy
Divide ₹600 in the ratio 2 : 3. The larger share is:	Easy
If 3 : x = 9 : 12, then x is:	Easy
The average of 10, 20, 30, 40 and 50 is:	Easy