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EasyExponentials & logarithms
OpenStax, Algebra and Trigonometry 2e §6.1 Exponential Functions · Example 9 · Algebra · Exponentials & logarithms

Using the Compound Interest Formula to Solve for the Principal

A 529 Plan is a college-savings plan that allows relatives to invest money to pay for a child’s future college tuition; the account grows tax-free. Lily wants to set up a 529 account for her new granddaughter and wants the account to grow to $40,000 over 18 years. She believes the account will earn 6% compounded semi-annually (twice a year). To the nearest dollar, how much will Lily need to invest in the account now?

~5 minWritten answer · compare with the solution

OpenStax, Algebra and Trigonometry 2e · §6.1 Exponential Functions · Example 9

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