Lily went for 8 rides at the county fair. Some rides were on the merry-go-round, and the rest were on the pirate ship. The total cost of all rides was $6.30. Each pirate ship ride cost $0.60, and each merry-go-round cost $0.90. How many pirate ship did Lily take?
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Let's assume Lily went on x pirate ship rides.
So, the number of merry-go-round rides she went on will be 8 - x.
The cost of pirate ship rides will be 0.60x, and the cost of merry-go-round rides will be 0.90(8 - x).
According to the given information, the total cost of all rides was $6.30.
So, we can write the equation as:
0.60x + 0.90(8 - x) = 6.30
Now, let's solve this equation to find the value of x.
0.60x + (0.90 * 8) - (0.90x) = 6.30
0.60x - 0.90x + 7.20 = 6.30
-0.30x + 7.20 = 6.30
-0.30x = 6.30 - 7.20
-0.30x = -0.90
Dividing both sides by -0.30:
x = -0.90 / -0.30
x = 3
Therefore, Lily took 3 pirate ship rides.
To determine the number of pirate ship rides Lily took, we need to find the number of rides on the merry-go-round first.
Let's assume Lily took x rides on the merry-go-round. Since she went for a total of 8 rides, the number of pirate ship rides can be found by subtracting the number of merry-go-round rides from 8.
Therefore, the number of pirate ship rides would be 8 - x.
Now, let's calculate the cost of all the rides. The cost of each merry-go-round ride is $0.90, so the total cost of merry-go-round rides would be 0.90x. Similarly, the cost of each pirate ship ride is $0.60, so the total cost of the pirate ship rides would be 0.60(8 - x).
Since the total cost of all the rides is given as $6.30, we can set up the following equation:
0.90x + 0.60(8 - x) = 6.30
Now, we can solve the equation to find the value of x, which represents the number of merry-go-round rides:
0.90x + 0.60(8 - x) = 6.30
0.90x + 4.80 - 0.60x = 6.30
0.30x + 4.80 = 6.30
0.30x = 6.30 - 4.80
0.30x = 1.50
x = 1.50 / 0.30
x = 5
Based on the calculation, Lily took 5 rides on the merry-go-round.
Finally, we can find the number of pirate ship rides by substituting the value of x into the equation 8 - x:
8 - x = 8 - 5 = 3
Therefore, Lily took 3 rides on the pirate ship.