Tanya purchased 4 hamners for $11.00 each and 7 scewdrivers for $6.65 each write an expresion for the total cost of the tools. then find the total cost

X=numbers of hammers

y=numbers of scewdrivers

f (x, y) = total cost in $

f (x, y) = 11x+6.65y

f (4,7) = 4 (11) + 6.65 (7) = 44+46.55=90.55

Sol: an expresion for the total cost of the tools is f (x, y) = 11x+6.65 y;

x=number of hammers

y = number of scewdrivers.

The total cost is $90.55

Total cost=cost of hammers+cost of screwdrivers

cost of hammers=number of hammers times cost per hammer

cost of screwdrivers=number of screwdrivers tiems cost per screwdriver

number of hammers=4

cost per hammer=11.00

number of screwdrivers=7

cost per screwdriver=6.65

subsiute

cost of hammers=4 times 11.00=44.00

cost of screwdrivers=7 tiems 6.65=46.55

total cost=cost of hammers+cost of screwdrivers

total cost=44.00+46.55=$90.55

total cost=$90.55