Friends go on a picnic and play "I ask you and answer" during the break. (1) Xiaohong asked: How much does it cost to buy a bag of melon seeds and a bag of jelly?

(1) 6.80+4.50 =11.3 (yuan);

Answer: It takes 1 1.3 yuan to buy a bag of melon seeds and a bag of jelly.

(2)20- 14.90=5. 1 (yuan),

6.80>5. 1>4.5,

A: You can buy a bag of melon seeds with the remaining money.

(3)6.80+4.50+ 14.90,

= 1 1.3+ 14.90,

=26.2 yuan;

Answer: It costs 26.2 yuan to buy these three kinds of food.

(4) Question 1: How much does it cost to buy three packs of jelly?

6.80×3=20.4 yuan;

A: It costs 20.4 yuan to buy three packs of jelly.

Question 2: How much is a bag of jelly more expensive than a bag of melon seeds?

6.80-4.50=2.3 (yuan);

A: A bag of jelly is more expensive than a bag of melon seeds, 2.3 yuan.