Solve with elimination:
10a + 4b = 18
7a + 14 = b
solve for b

You put $2000 in an account with a simple interest rate of 1.5%. how long does it take for the account to earn $60?

In a box lenght 1m breadth 60 cm and height 40 cm small rectangular packets of dimension 5 cm into 8 cm into 10 cm are packed. how many such small packets can be packed in the big box?

The sum of the squares of two numbers is 8 . the product of the two numbers is 4. find the numbers.