The original price of a stereo was reduced by 40%. the sales price was then reduced by 25%. this price was then reduced by 35%. if a stereo is now selling
for $234.00, what was the original price?

If it was reduced by 35% 234  is 65% of the reduced price. So you divide it by 65 and multiply by 100.
234/65 x 100 = 360
360 is the price that was reduced by 25 % so it's 75% of the reduced price. for this you do 360 / 75 x 100 = 480
480 is the price that was reduced by 40% so it is 60% of the original price. to find the original price you do 480/60 x 100 = $800