PIG5 = [$23,000,000/1.10 + $29,000,000/1.102 + $21,000,000/1.103]/$35,000,000 = 1.73
PIWi–Fi = [$23,000,000/1.10 + $42,000,000/1.102 + $39,000,000/1.103]/$55,000,000 = 1.54
NPVG5 = –$35,000,000 + $23,000,000/1.10 + $29,000,000/1.102 + $21,000,000/1.103
NPVG5 = $25,653,643.88
NPVWi–Fi = –$55,000,000 + $23,000,000/1.10 + $42,000,000/1.102 + $39,000,000/1.103
NPVWi–Fi = $29,921,111.95
NPVL6 and G5 = $11,141,998.50 + 25,653,643.88
NPVL6 and G5 = $36,795,642.37
This is greater than the Wi-Fi project, so we should accept the L6 project and the G5 project.
Cumulative cash flows Year 1 = $370,000 = $370,000
Cumulative cash flows Year 2 = $370,000 + 310,000 = $680,000
Payback period = 1 + ($650,000 – 370,000)/$310,000 = 1.90 years
Cumulative cash flows Year 2 = $490,000 + 460,000 = $950,000
Payback period = 2 + ($975,000 – 950,000)/$410,000 = 2.06 years