Quick and dirty solution, rounding the final value to the nearest cent.

assumption: investment is made at the end of the month

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Her monthly contribution = $2,461 * 9.5% = 233.795

Company match = $2,461 * 5.4% = 132.894

Total investment per month = 366.689

interest rate per month = 8.1% / 12 = .675% / month

Number of periods = 25 * 12

using Excel FV function (with "type"=1), you get $88,798.898 which would round to $88,798.90

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But any real financial institution will round the employee and employer contribution to the nearest cent

Monthly contribution = 233.80+132.89 = 366.69

....and then it would round the increase every month,

so that at the end of the first period it would be 366.69

at the end of the second period it would be 735.86 (instead of a mathematically correct 735.8552) and I'm not going to figure out the other 298 intermediate values.

sorry for all the stuff below the dashed line, but I wanted you to know about the complexities in the real world.

Note: FV = A (1 + i/12)^nper - 1

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i/12

where nper in this case is 25 years * 12 payments/year and i/12 is the monthly interest rate