Answer:
150 oz.
Step-by-step explanation:
There are already 150 ounces of alloy of nickel.
Of this 150 oz, 70% is pure i.e. nickel content = 150(0.7) = 105 oz
Now available is
Nickel Other metals
105 45
Let x oz of pure nickel is added.
Then new alloy will have 105+x oz nickel in total of 150+x oz.
Percentage pure =
Simplify to get
Hence answer is 150 oz should be added.
Answer:
First graph (see below)
Step-by-step explanation:
The graph of the arctan(x) is the first graph attached, see below. This is because if you were to plug in the equation in any TI calculator, you would get this graph.
Answer:
The expected combined weight of the child's lollipop and two chocolate bars is 5.5 oz.
Step-by-step explanation:
Normal probability distribution
When the distribution is normal, we use the z-score formula.
In a set with mean and standard deviation
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Addition of normal variables:
The mean is the sum of the means.
Find the expected combined weight of the child's lollipop and two chocolate bars.
Child lollipop: Mean 1.5 oz
Chocolate bars: Mean 2 oz
One lollipop and 2 bars combined
The mean will be 1.5 + 2*2 = 5.5 oz
The expected combined weight of the child's lollipop and two chocolate bars is 5.5 oz.