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I have tried to solve this following question but I find it quite difficult for myself. Maybe it is because of the wording of the question.

- A kangaroo that is 1.2 m tall can jump a distance of 9 m. What percent of the kangaroos's height does the length of one of its jumps represent?

Percentages can seem a little tricky at first. When you calculate a percentage, what you are doing is representing a multiplying factor using the notation of a percent. Start with an amount, say x, and multiply it by a factor f to get y; that is

y = x･f,

you now want to represent f = y/x as a percent, p. To do this, calculate

p = (f-1)･100%.

Thus if x increases by a factor of 2 (i.e., it doubles), then y = 2x so that f = 2 in this case. So p = (2-1)･100 = 100%. So x has increased by 100%.

For your problem, the x = height = 1.9m and y = distance of jump = 9m. Since y = x･f, we have f = y/x = 9m/1.2m = 7.5, so that

p = (7.5-1)100% = 600%.

Randy

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#### randy patton

##### Expertise

college mathematics, applied math, advanced calculus, complex analysis, linear and abstract algebra, probability theory, signal processing, undergraduate physics, physical oceanography

##### Experience

26 years as a professional scientist conducting academic quality research on mostly classified projects involving math/physics modeling and simulation, data analysis and signal processing, instrument development; often ocean related

Publications
J. Physical Oceanography, 1984 "A Numerical Model for Low-Frequency Equatorial Dynamics", with M. Cane

Education/Credentials
M.S. MIT Physical Oceanography, B.S. UC Berkeley Applied Math

Past/Present Clients
Also an Expert in Oceanography