Since they are in ratio we have, 3X + 5x/2 +7x/10 =155 ( since 50 paise is half of a rupee and 10 paise is 1/10 of a rupee. After taking L C M and cancellations we get, X= 25 So we get , 75one rupee coins and 125 fifty paise coins and 175 ten paise coins. Checking: 75+62.5+17.5=155 Hope it helps .... Have any doubts pls ask