Macey bought three kinds of candy in the supermarket, including red candy 8 cents, green candy/kloc-0 cents and yellow candy 2 cents. She spent 65438+2 cents on 0 yuan.

According to the above analysis, at least four pieces of brown sugar are needed to make her pay 1 yuan 20.2 points.

1 yuan, 22 cents = 122 cents, 1 angle = 10 cents, 2 cents =20 cents.

122-8×4,

= 1 12-32,

=90 (minutes),

90=20×2+ 10,

So Macey should buy at least 4 red sweets, 1 green sweets and 4 yellow sweets.

4+ 1+4=9 (grains).

So the answer is: 9.