Pre Algebra
posted by INEEDHELP! :( on .
Find the Original Amount:
NEW AMOUNT: 210
75% INCREASE
**please help me as soon as possible and explain steps please!**

please help me!!!!!!!!!! i have to turn in the assignment in an hour and i don't get this problem please explain and help me pleaseeeeeeeeeeeeeeeeeeeeeeeeeeeeee!!!!!!!1

75% increase over 100% is 175%
Use direct proportion:
175% : 210
100% : ?
Cross multiply to get:
100%*210/175%
= 120
Check:
120*(100%+75%)=210, OK