Question 1: It is known that the refrigerator is 2480 yuan, the fan is 326 yuan, the washing machine is 668 yuan, and the TV set 1980 yuan.

How much is the refrigerator more expensive than the electric fan?

(2480-326)/326=66 1%

How much cheaper is a washing machine than a TV set?

( 1980-668)/ 1980=66.3%

How much is the refrigerator more expensive than the TV?

(2480- 1980)/ 1980=25.3%

Television is cheaper than refrigerator. how much is it? )

(2480- 1980)/2480=20.2%

Question 2: What percentage of boards may be wasted when a board with a length of 1 m and a width of 8 mm is processed into the largest circular desktop?

Wood used is: 3. 14 * 4 2 = 50.24.

Waste wood: 80-50.24=29.76.

So wasted boards: 29.76/80=37.2%

Question 3: Uncle Li is going to buy a house. During the consultation, he learned that if the installment payment is a price increase of 15% and a one-time payment is 10% off, the installment payment will cost 40,000 yuan more than the cash purchase. How much is this house?

The overpayment accounts for 25% of the house price, that is, 40 thousand yuan.

So this house is 4/25% = 1.6 million.