Answer:X=13/145
Step-by-step explanation:
Answer:
1539
Step-by-step explanation:
We solve the above question using the Exponential decay formula
= A(t) = Ao(1 - r) ^t
Ao = Initial Amount invested = 7600
r = Decay rate = 55% = 0.54
t = time in weeks = 2
Hence:
A(t) = 7600(1 - 0.55)²
A(t) = 7600 × (0.45)²
A(t) = 1539
Therefore, the value of the quantity after 2 weeks is 1539
Answer:
The least squares method results in values of the y-intercept and the slope, that minimizes the sum of the squared deviations between the observed (actual) value and the fitted value.
Step-by-step explanation:
The method of least squares works under these assumptions
- The best fit for a data collection is a function (sometimes called curve).
- This function, is such that allows the minimal sum of difference between each observation and the expected value.
- The expected values are calculated using the fitting function.
- The difference between the observation, and the expecte value is know as least square error.
175 mL at 25% concentration of alcohol contains 0.25 (175 mL) = 43.75 mL of alcohol. If <em>v</em> is the amount of the 70% solution that you use, then that amount contains 0.7<em>v</em> mL of alcohol.
Mixing these two yields a total volume of 175 mL + <em>v</em>, and it contains 43.75 mL + 0.7<em>v</em> alcohol. You want to end up with a concentration of 45%, which means the ratio of the amount of alcohol to the total volume needs to be 0.45:
(43.75 mL + 0.7<em>v</em>) / (175 mL + <em>v</em>) = 0.45
Solve for <em>v</em> :
43.75 mL + 0.7<em>v</em> = 0.45 (175 mL + <em>v</em>)
43.75 mL + 0.7<em>v</em> = 78.75 mL + 0.45<em>v</em>
0.25<em>v</em> = 35 mL
<em>v</em> = 140 mL
