At a Birthday party as many Masala Dosas as is the cost of a plain dosa and as many plain dosas as is the cost of a masala dosa were ordered. If the total bill for the masala and plain dosas is Rs 1000 , then in how many ways could they have ordered the plain and masala dosa ?

• 12 ways.
  
  Let there be 'x' masala dosa and 'y' plain dosa ordered.
  => Let Price of 1 masala dosa = x
  => And price of 1 plain dosa = y
  => xy + yx = 1000
  => 2xy = 1000
  => xy = 500 = 2^2 * 5^3
  => 500 has 3*4 = 12.
• 12 years agoHelpfull: Yes(2) No(1)
• m*p+p*m = 1000
  2mp=1000
  mp=500 = 2^2 * 5^3
  
  so 3*4= 12 possible ways
• 12 years agoHelpfull: Yes(1) No(0)