Answer:
Douglas can race the go-karts at least 3 times.
Step-by-step explanation:
Given that:
Worth of game card = $20
Cost of go-kart = $3.50 each time
Amount Douglas wants to left = $7.75
Let,
x be the times Douglas can ride go-kart.
20 - 3.50x ≤ 7.75
-3.50x ≤ 7.75 - 20
-3.50x ≤ -12.25
3.50x ≤ 12.25
Dividing both sides by 3.50
[tex]\frac{3.50x}{3.50}\leq \frac{12.25}{3.50}\\x\leq 3.5[/tex]
Hence,
Douglas can race the go-karts at least 3 times.
Douglas should race 3 or fewer times to make sure he has at least $7.75 left on his card.
Given to us
Douglas bought a $20 game card at a game center.
The go-karts cost $3.50 each time you race.
Douglas wants to have at least $7.75 left on his card to play arcade games.
Assumption
Let's assume that Douglas races x number of times on go-kart.
As we know the total balance on the card is $20. And the cost of go-karts is $3.50 each time we race. Also, we need to save $7.75 on the card, therefore, Inequality can be written as,
$20 - ($3.5)x ≤ $7.75
$20 - ($3.5)x ≤ $7.75
[tex]20 - (3.5)x \leq 7.75\\\\-3.5x \leq 7.75-20\\\\-3.5x \leq -12.25\\\\x \leq \dfrac{-12.25}{-3.5}\\\\x \leq 3.5[/tex]
Hence, Douglas should race 3 or fewer times to make sure he has at least $7.75 left on his card.
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