Jerry had 35 big stickers and 20 small stickers at first, which means that he had a total of 55 stickers. After exchanging 10 small stickers for 5 big stickers, he would have 30 small stickers and 40 big stickers.
To find the percentage of big stickers, we can use the following formula:
Percentage of big stickers = (Number of big stickers ÷ Total number of stickers) x 100%
Plugging in the numbers, we get:
Percentage of big stickers = (40 ÷ 70) x 100%
Percentage of big stickers = 57.14%
Therefore, the closest answer to the percentage of big stickers in the end is (4) 80%.