A customer’s loyalty card at a store gives them rewards of $1 off their next purchase for every $20 they spend. Their last shopping trip, they spent $80. This shopping trip, they spent $43, used their rewards, and applied a coupon that took twice the amount of rewards off the price. How many dollars did the customer pay on this shopping trip?
The customer had 80 / 20 = $
<gadget id="calculator">80/20</gadget>
<output>4</output>
4 in rewards.
Their coupon was worth 4 * 2 = $
<gadget id="calculator">4*2</gadget>
<output>8</output>
8.
Thus, they paid 43 - 4 - 8 = $
<gadget id="calculator">43-4-8</gadget>
<output>31</output>
31 on this shopping trip.

<result>31</result>