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The wavelength \(W\) of a radio wave varies inversely as its frequency \(F\) A wave with a frequency of 1200 kilohertz has a length of 300 meters. What is the length of a wave with a frequency of 800 kilohertz?

Find an equation of variation in which: \(y\) varies directly as the square of \(x,\) and \(y=50\) when \(x=10\)

Explain why it is essential to check any possible solutions of rational equations.

Explain the difference between adding rational expressions and solving rational equations.

When two rational expressions are added or subtracted, should the numerator of the result be factored? Why or why not?

Simplify. Do not use negative exponents in the answer. $$ \frac{24 a^{-4} c^{-8}}{16 a^{5} c^{-7}} $$

The intensity I of light varies inversely as the square of the distance \(d\) from the light source. The following table shows the illumination from a light source at several distances from the source. What is the illumination 2.5 ft from the source?

Find the \(L C M\) The LCM of two expressions is \(8 a^{4} b^{7}\). One of the expressions is \(2 a^{3} b^{7}\). List all the possibilities for the other expression.

Young's rule for determining the size of a particular child's medicine dosage \(c\) is $$c=\frac{a}{a+12} \cdot d$$ where \(a\) is the child's age and \(d\) is the typical adult dosage. If a child's age is doubled, the dosage increases. Find the ratio of the larger dosage to the smaller dosage. By what percent does the dosage increase?

A peanut butter jar in the shape of a right circular cylinder is 4 in. high and 3 in. in diameter and sells for \(\$ 2.40 .\) If we assume that cost is proportional to volume, how much should a jar 6 in. high and 6 in. in diameter cost?