Four people each have a different willingness to pay for one unit of a good: George will pay $15, Glen will pay $12, Tom will pay $10, and Peter will pay $8. If price decreases from $9 to $8 then the consumer surplus from this unit will increase by___. The consumer surplus is calculated as the marginal benefit or the value of the good minus its price, then summed over the quantity bought. If the price is $9, there are only 3 people (George, Glen, and Tom) who would buy the goods. Since Peter wants to pay $8, he will not buy this good since its price ($9) is higher than his willingness to pay. The consumer surpluses for George, Glen, and Tom are $6 (=15 - 9), $3 (=12 - 9), and $1 (=10 - 9), respectively. The total consumer surplus would be $10 (= 6 + 3 + 1). If the price is $8, all of them would be willing to buy the goods. The consumer surpluses for George, Glen, Tom, and Peter are $7 (=15 - 8) $4 (=12 - 8), $2 (=10 - 8), and $0 (=8 - 8), respectively. The total consumer surplus would be $13 (= 7 + 4 + 2). Thus, if price decreases from $9 to $8 then the consumer surplus from this unit will increase by $3. If the price increases from $9 to $11, what would be the decrease in consumer surplus?

total consumer surplus = ($15 + $12 + $10 + $8) - (4 x $8) = $45 - $32 = $13. Consumer surplus is the difference between the maximum amount that consumers are willing to pay for a good or service, and its actual price.

when the price was $9 per unit, total consumer surplus = ($15 + $12 + $10) - (3 x $9) = $37 - $27 = $10.

that means that consumer surplus increased by $13 - $10 = $3