A bag contains coins of 1 rupee, 50 paise and 25 paise in the ratio of 1 : 2 : 4. If the total money in the bag is ₹ 225, then how many 50 paise coins are there?

150

Denomination - 1rupee : 50 paise : 25 paise 

                            1    :     2       :     4

Total Amount = (1 x r) + (0.50 x 2r) + (0.25 x 4r) = 225

                          r + r + r = 225       

                                  3r  = 225  ⇒ r = 75

No. of 50 paise coins = 2r = 2 x 75 = 150