Question

Writing to Explain A marine biologist is preparing a tank of

sea creatures for a demonstration. The tank includes 20% sea
urchins, 10% sea squirts, 40% starfish, and 30% anemones.
Of the starfish, 30% have more than 5 arms. There are a total
of 50 creatures in the tank. How many starfish have more
than 5 arms? Jordan says 14 starfish have more than 5 arms.
Explain whether Jordan's answer is reasonable.

Answer 1

To find the number of starfish with more than 5 arms, we need to first calculate the total number of starfish in the tank and then find 30% of that number.

To calculate the total number of starfish in the tank, we need to multiply the total number of creatures by the percentage of starfish:

Total number of starfish = 40% of 50 creatures = 0.4 x 50 = 20 starfish

To find the number of starfish with more than 5 arms, we need to multiply the total number of starfish by the percentage of starfish with more than 5 arms:

Number of starfish with more than 5 arms = 30% of 20 starfish = 0.3 x 20 = 6 starfish

Therefore, the correct answer is that there are 6 starfish with more than 5 arms.

Now, let's consider whether Jordan's answer of 14 starfish with more than 5 arms is reasonable. Since we know that there are only 20 starfish in the tank, it is highly unlikely that 14 of them would have more than 5 arms, especially since we know that only 30% of starfish have more than 5 arms. Therefore, Jordan's answer is not reasonable and is likely the result of a calculation error. It is important to double-check calculations and consider whether answers make sense based on the given information.