Annual dollar use is the exact product of demand and unit cost.

highlighted = computed this step

X annual use

X annual dollar use is 60.

useX=60\text{use}_X=60
Annual dollar useAnnual dollar use is demand times unit cost for each item.annual dollar useuseX60Y40W30Z20

Y annual use

Y annual dollar use is 40.

useY=40\text{use}_Y=40
Annual dollar useAnnual dollar use is demand times unit cost for each item.annual dollar useuseX60Y40W30Z20

W and Z

W annual use is 30 and Z annual use is 20.

useW=30useZ=20\text{use}_W=30\quad \text{use}_Z=20
Annual dollar useAnnual dollar use is demand times unit cost for each item.annual dollar useuseX60Y40W30Z20

Total use

Total annual dollar use is 150.

total use=150\text{total use}=150
Annual dollar useAnnual dollar use is demand times unit cost for each item.annual dollar useuseX60Y40W30Z20