Quantitative Aptitude - Arithmetic Ability Questions

Of the 5 numbers whose average is 72, the first is 1/8 times the sum of other 4. The first number is _____.

The point P(a, b) is first reflected in origin to P1 and P1 is reflected in Y-axis to (4, -3). What are the co-ordinates of point P?

20% discount is offered on an item. By applying a promo code the customer wins 10% cash back. What is the effective discount?

By increasing the price of entry ticket to a fair in the ratio 11:16, the number of visitors to the fair has decreased in the ratio 19:9. In what ratio has the total collection increased or decreased?

An army of 12000 consists of Europeans and Indians. The average height of a European is 5ft 10 inches and that of an Indian is 5ft 9 inches and that of the whole army is 5ft 9 3/4 inches. Then the number of Indians in the army is ?

Find the LCM of 0.63, 10.5, 2.1, 4.20

HCF and LCM of two numbers are 11 and 825 respectively. If one number is 275 find the other number.

In each of the following questions two equations I and II are given. Solve both the equations and give answer:
$$\begin{gathered} I. x2+2x-195=0 \\ II. y2+30y+225=0 \end{gathered}$$