Let x be the number of 5 points question.
Let y be the number of 2 points question.
Total number of questions is 38
x + y = 38
Total points is 100
5x + 2y = 100
x + y = 38 ------------- (1)
5x + 2y = 100 ---------(2)
From (1):
x + y = 38
x = 38 - y -------------- sub into (2)
5(38 - y) + 2y = 100
190 - 5y + 2y = 100
3y = 90
y = 30 ------------------ sub into (1)
x + 30 = 38
x = 38 - 30
x = 8
There are 8 5-point questions and 30 2-point questions
Answer:
D. 150 metres
Step-by-step explanation:
speed = (60) times 5/18 = 50/3
lenght of the train = (speed x time)
lenght = 50/3 times (9)
= 150 m.
<span>B. 285/302. This is the correct answer because it is the only choice which is roughly the same ratio as 47.5/50.5 which is the ratio needed to determine how long it would take to go 47 1/2 miles in a car that averages 50 1/2 miles per hour. The mathematical equation which represents the problem is: 50.5/1 = 47.5/A (A = hours) which is the same as 50.5 A = 47.5 which means A = 47.5/50.5 which means A = .94 hours. 285/302 also equals .94.</span>
Answer:
144.2 cm
Step-by-step explanation:
Length of the iron rod is 7.4cm
Radius is 3.1m
Therefore the surface area can be calculated as follows
= 2πrl
= 2×3.142×3.1×7.4
= 144.2 I'm
Hence the surface area is 144.2cm
Answer: x=-6
Step-by-step explanation:
Let's solve your equation step-by-step.
2(9−x)=3(x+16)
Step 1: Simplify both sides of the equation by distribution
Step 2: Subtract 3x from both sides.
Step 3: Subtract 18 from both sides.
Step 4: Divide both sides by -5.
