Let the second score = x
⇒ second score = x
<span>the first is 14 points more than the second
</span>⇒ first score = x + 14
<span>the sum of the first two is 6 more than twice the third
</span>⇒ third score = 1/2 (x + x + 14 - 6) = x + 4
<span>The sum of a student's three score is 246
</span>⇒ x + (x + 14) + (x + 4) = 246
<span>
Solve x:
</span>x + x + 14 + x + 4 = 246
3x + 18 = 246
3x = 228
x = 76
second score = x = 76
first score = x + 14 = 76 + 14 = 90
Answer: 90
Answer: speed of the car is 88 miles per hour
the speed of the motorcycle is 78 miles per hour
Step-by-step explanation:
Number of miles travelled by car = 312
Number of miles travelled by motorcycle = 272
Let x = speed of the car
Let y = speed of the motorcycle
If the car's speed is 10mph more than the motorcycle's, it means
x = y + 10 - - -- - - 1
Time taken for car to travel 312 miles is distance /speed = 312/x
Time taken for motorcycle to travel 272 miles is distance /speed = 272/y
The car travels 312 miles in the same time that a motorcycle traveled 272.
This means
312/x = 272/y
312y = 272x
y = 272x/312
Substituting y = 272x/312 into equation 1, it becomes
x = 272x/312 + 10
312x = 272x + 3120
312x-272x = 3120
40x = 3120
x = 3120/40 = 78 miles per hour
x = y + 10 = y + 78
x = 88 miles per hour
3(4*3)=12*9
12*9=108
3(4*3)=3*4=12
3*3=9
12*9
Answer:
1 and 3 is right and I’m pretty sure 2 is right also.
Step-by-step explanation:
The correct answer is 6,8
