From clue 3, we know that the three numbers average to 15. This means we add up the three numbers x,y and z and divide by 3 to get 15. So one equation is (x+y+z)/3 = 15 which turns into x+y+z = 45 after multiplying both sides by 3.
Let's say that x < y < z. In other words x is the smallest number, y is the middle and z is the largest. Based on clue 2, this would tell us that z = 8*x (since largest is 8 times the smallest). We can replace the 'z' in the equation x+y+z = 45 with 8x like so
x+y+z = 45
x+y+8x = 45 ... replace z with 8x
9x+y = 45
Now onto clue #1. The smallest number x is a prime number and it is 1/6 times the size of the middle number y. Put another way, the middle number y is 6 times larger than the smallest number. We have this equation y = 6*x
9x+y = 45
9x+6x = 45 ... replace ywith 6x
15x = 45
x = 45/15
x = 3 which is a prime number
Now that we know x = 3, we can use it to find y
y = 6*x = 6*3 = 18
and then use x = 3 to find z
z = 8*x = 8*3 = 24
Therefore the three mystery numbers are 3, 18, and 24. Note how these three values add to 3+18+24 = 45 which you then divide over 3 to get 45/3 = 15. So the average of the values 3, 18, 24 is the number 15. This helps confirm the answer.
Answer:
3 hours
Step-by-step explanation:
After one hour, car a will be only 20 miles ahead of car b, after two hours, car a will only be 10 miles ahead of car b, and after 3 hour, they will both be equal. This is because car b is going 10 mph faster than car a, because 70-60=10. every hour, car b will catch up to car a by 10 miles.
Leave a thanks if I am correct
Answer:
30
Step-by-step explanation:
Problem = 3x + 21 for x=3
3(3) +21 --- subsitute the three for the x
9 + 21 ---- multiply the 3s together
30 ----- add
All exterior angles of a regular polygon would equal 360 degrees. SO... based on that, one exterior angle would have to multiplied by whatever sum (whole number) to equal 360 degrees to find the number of sides. Here you divide 360 by one of the exterior angles, if it does not equal a whole number then it would be inaccurate.
In this case only 54 degrees would not fit into one of the exterior angles.
