While in math class, Trunks is called on to solve a math problem: (1000 - 900 * 0.5). Trunks attempts to subtract 900 from 1000 first, but Pilaf interrupts him and correctly states that he must multiply 900 by 0.5 first then subtract the result from 1000. To make his point more tangible, Pilaf uses an example involving a sale.
Elaine goes out with a salesman who offers her a discount on a dress. He wants sex, but would prefer for her not to take advantage of the discount—he's dangling it in front of her as an incentive. She wants the discount, but would prefer not to have to sleep with him for it—she'd dangling it in front of him as an incentive. Both stall the other....and achieve a suboptimal social outcome. Kramer says "you need to establish trust before you can have a free exchange of sex...and discounts, the cornerstones of a healthy relationship."