A and b are the minutes spent on machine A and machine B, respectively.
a+b = 40
b = 40-a
8a + 6b = 300
8a + 6(40-a) = 300
8a + 240 - 6a = 300
2a = 60
a = 30
b = 40-a = 10
30 minutes on machine A and 10 minutes on machine B
Answer:
2.5cm^2
Step-by-step explanation:
so diameter is basically radius*2...to find radius(since area of circle is pi*r^2 we need to divide diameter by 2)
so 1.8/2=0.9
now,
pi*0.9^2
pi*0.81
2.5 cm^2
Answer:
at least 17
Step-by-step explanation:
if you add and shid it kinda like division multiplied by 10. ya know
2 1/4 + 1 1/2
2 + 1 = 3
1/4 + 1/2 = 1/4 + 2/4 = 3/4
so ur answer is 3 3/4 lbs of cheese in total
Answer:
The rate charged by first mechanic per hour= x =$85
The rat charged by second mechanic per hour =y = $70
Step-by-step explanation:
Two mechanics worked on a car. The first mechanic worked for 10 hours, and the second mechanic worked for 15 hours. Together they charged a total of $1900. What was the rate charged per hour by each mechanic if the sum of the two rates was $155 per hour?
Solution
Let
x= hourly rate of the first mechanic
y= hourly rate of the second mechanic
Derive two equations to solve for the two unknowns
10x + 15y = 1900 (1)
x + y = 155 (2)
From (2)
x + y = 155
x=155-y
Substitute x=155-y into (1)
10x + 15y = 1900
10(155-y) + 15y =1900
1550 -10y + 15y =1900
5y =1900-1550
5y=350
Divide both sides by 5
y= 70
Substitute y=70 into (2)
x + y = 155
x + (70) =155
x=155 - 70
= 85
x= 85
The rate charged by first mechanic per hour= x =$85
The rat charged by second mechanic per hour =y = $70