Installation Schedule

Building A

X

Can't happen first

Building B

Must happen before Building D

Building C

Must include the $12$th in the schedule

Building D

Must happen before Building A

Question

New security systems must be installed on $4$ buildings, one at a time. Installation takes $4$ days. The installers do not start a new job on Mondays or work weekends. On which date should the work on Building A begin, to complete all $4$ buildings as early as possible?

Calendar

SUN

MON

TUE

WED

THU

$4$

FRI

$5$

SAT

$6$

$22$ of $24$

Question

New security systems must be installed on $4$ buildings, one at a time. Installation

takes $4$ days. The installers do not start a new job on Mondays or work weekends.

On which date should the work on Building A begin, to complete all $4$ buildings as

early as possible?

Calendar

SUN

MON

TUE

WED

THU

FRI

SAT

$1$

$2$

$3$

$4$

$5$

$6$

$7$

$8$

$9$

$10$