Respuesta :

100+70=170
200 times 1.70=340
increase by 10%
10% of 340 is 34
add that
340+34=374

374/200= what percent?
374/200=187/100=187%

answer is 187%
200*1.7=340
340*1.1=374
(374-200)/200
174/200=0.87 
0.87*100=87
87%+100%=187%

Hope this helps :)