The price of an item has dropped to $42 today. Yesterday it was $140. Find the percentage decrease.

Sure, here are the steps to find the percentage decrease:

1. First, find the difference in price from yesterday to today. This is done by subtracting the new price from the old price. So, $140 -$42 = $98. This is the amount the price has decreased.

2. Next, to find the percentage decrease, divide the decrease by the original price (the price from yesterday). So, $98 /$140 = 0.7.

3. Finally, to convert this number into a percentage, multiply by 100. So, 0.7 * 100 = 70%.

Therefore, the price of the item has decreased by 70%.