How do I solve this using the Purchasing Power Preservation?

Years Until Retirement

Years in Retirement

Investment Rate of return$/$year

Inflation$/$year

Estimated wage $\%$ growth$/$year

Estimated Retirment Income Needs $($In Today's Dollars$)$

Expected Retirement Income Benefits That Are Adjusted For Inflation:

$1.)$ Expected annual Social Security Income $($In Today's Dollars$)$

Expected annual pension income $($In Today's Dollars$)$

Expected Retirement Income Needed From Savings

Current Value of Savings

How