If sec -5π/4 = x, then  the value   of x is

A wholesaler had 200 dozen of mangoes. He sold some of these mangoes at 20 % profit and the rest at 10 % profit, so that he made 13 % profit on selling all the mangoes. How many mangoes in dozens) did he sell at 20 % profit? 

Megha invests an amount of Rs. 15,860 in the names of her three daughters A, B and C in such a way that they get the same interest after 2, 3 and 4 years respectively. If the rate of simple interest is 5 % p.a, then the ratio of the amounts invested among A, B and C will be – 

A person invested some amount at the rate of 12 % simple interest and a certain amount at the rate of 10 % simple interest for 1 year. He received yearly interest of Rs. ₹ 130, but if he had interchanged the amount invested, he would have received 4 more as interest. How much did he invest at 12 % simple interest? 

If the simple interest on a certain sum of money for 2 years in one fifth of the Principal, then find rate of interest per annum. 

Ankur borrowed sum money from Megha at 8 % P.a simple interest and twice the amount from Harshita at 9 % P.a simple interest. He then added some more money of his own and lent the entire amount to Shalini at 10 % p.a simple interest. At the end of the year Ankur gained 14,000. If Ankur lend ₹ 40,000 to Shalini, then how much did Ankur borrow from Megha ? 

A sum of ₹ 1750 is divided into two parts such that the interests on the first part at 8 % simple interest per annum and that on the other part at 6 % simple interest per annum are equal. The interest on each part (in rupees) is 

A certain sum becomes Rs. 1020 in 5 years and Rs. 1200 in 8 years at simple interest. What is the value of principal?