Why Are Calculations of Growth in Salmon Smolt Showing Different Results?

[Newton86]

urgent. Growth in salmon smolt

Homework Statement

smolt weith is 35g we shall find the weight after 61 days.

Homework Equations

specific growth rate:; K' = Ln (N2 / N1) / (t2 - t1)
growth rate is 1,9 %

The Attempt at a Solution

I find 110g when I use this forumula 35g*1,019^61
But Others have found 115g as answer. So I am confused. My formula might not be valid for this ?

also if I use this calculator and put in 1 day 35g and 61 day 110 g The growth rate is only 1.87 and with 115g its 1,95 but with 112g its 1.9 So if this calculator is correct 112g the right answer ?

Please answer if you understand. Its probably a easy task I am just so confused

 

[AvroArrow]

. The correct answer is 115g, using your equation. You can use the calculator to check your results. When you input 1 day as 35g and 61 days as 110g, the growth rate is only 1.87 because you are not accounting for the additional days in between. You must use the equation to account for all of the days, not just the start and end.

 

[baba89]

I would first like to clarify the context of the problem. Is this growth in salmon smolt being observed in a controlled environment, such as a laboratory or fish farm, or in the wild? This information is important because it can affect the accuracy of the growth rate calculation.

Assuming this is a controlled environment, the formula you have used to calculate the specific growth rate is correct. However, there are a few factors that could explain the discrepancy in the calculated weight after 61 days. First, the specific growth rate may not remain constant throughout the 61-day period. Growth rate can be affected by various factors such as food availability, water quality, and temperature. Therefore, the growth rate may have changed since the initial measurement of 35g. Additionally, there may be errors in the initial measurement or in the 61-day measurement, which can also affect the calculated weight.

Furthermore, the growth rate you have provided (1,9%) is a percentage, not a decimal. When using the formula, you should use the decimal equivalent of the percentage, which is 0.019. This could explain the slight difference in the calculated weight.

In terms of the calculator, it is possible that it uses a different formula to calculate the growth rate. It is always important to double-check the accuracy of formulas and calculations when working with scientific data.

In conclusion, to accurately determine the weight after 61 days, it would be best to take multiple measurements throughout the 61-day period and calculate the average growth rate. This will provide a more accurate estimate of the weight. Additionally, it is important to consider all possible factors that may affect the growth rate in order to accurately interpret the results.