Answer:
$1800
Step-by-step explanation:
First, rewrite out the information you already have:
-for 4 hrs-cost $850
-for 7 hrs-cost $1300
-for 12 hrs-$?
Next, we have to find out the amount of cost for hire per hour, so we can multiply that by 12 hrs:
-start by subtracting $850 from $1300:
1300-850=$450
-now subtract 4 hrs from 7 hrs:
7-4=3 hrs
In doing this, we see that the cost for 3 hrs hire is $450. Now, to find the unit cost per hr hire, divide $450 by 3 hrs:
450÷3=$150/hr
It costs $150 per hr hire.
Now, we have to find the cost for 12 hrs hire, so just multipy the unit cost by 12:
150*12=$1800 for 12 hrs hire
It costs $1800 for 12 hrs hire.
Answer:
#2,050
Step-by-step explanation:
Firstly bring out d information you av
C=a+bT (where a and b are constants)
Substitute the given values in the equations
#850=a+4b....(1)
#1300=a+7b......(2)
Subtract equation(1) from equation (2)
giving us: -#450=-3b
Divide both sides by -3
which gives: b=#150
Substitute #150 for b in equation(1)
#850=a-4b
#850=a+4(#150)
#850=a+#600
collect like terms
#850-#600=a
a=#250
.a=#250,b=150
C=a+bT
Substitute #250 and #150 for a and b in the equation above
C=250+150T(formula connecting C and T)
C=?, T=12hrs
C=#250+#150(12)
C=#250+#1800
....C=#2050
