Quantitative Aptitude - Arithmetic Ability Questions

The marked price of a pen is Rs 3000. The shopkeeper gives two successive discounts of 15% and a% to the customer. If the customer pays Rs 2142 for the pen, then what is the value (in percentage) of a?

When a number is increased by 26, it becomes 113% of itself. What is the number?

What is the value of Sin 30- √2 Cos 30

There is 40% increase in an amount in 8 years at simple interest. What will be the compound interest (in rupees) of Rs 30000 after 2 years at the same rate?

The income of P, Q and R are in the ratio of 5 : 4 : 3 respectively and their expenses are in the ratio of 6 : 5 : 4 respectively. If P saves Rs 4000 out of an income of Rs 10000, then what will be the saving (in Rs) of Q?

Working together, pipes A and B can fill an empty tank in 10 hours. They worked together for 4 hours and then B stopped and A continued filling the tank till it was full. It took a total of 13 hours to fill the tank. How long would it take A to fill the empty tank alone?

ABCD is a quadrilateral in which BD and AC are diagonals then

Rs. x invested at 9% simple interest per annum for 5 years yields the same interest as that on Rs. y invested at 6.25% simple interest per annum for 8 years. Find x:y.