A sum of '8550 is to be paid in 15 installments where each installment is '10 more than the previous installment. Find the first installment and the last installment.
A salesman is known to sell a product in 3 out of 5 attempts. While another salesman in 2 out of 5 attempts. Find the probability that a. No sales will happen b. Either of them will succeed in selling the product.