A financial planner wants to compare the yield of income and growth mutual funds. $\$50,000$ is invested in each of $35$ income and $40$ growth funds.
The mean increase for a two-year period for the income funds is $\$900$.
For the growth funds, the mean increase is $\$875$.
Income funds have a population standard deviation of $\$75$.
Growth funds have a population standard deviation of $\$65$.
The financial planner would like to know if there is a difference in the mean yields of the two funds.
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