Answer:
The last quiz score must be at least an 80 to get the average to be a 70.
Step-by-step explanation:
In order to find this, you need to take the average of the 4 test scores along with the unknown test score (x). So, to find an average, we add all the numbers together and divide by the amount of tests taken. We can then set this equal to 70 since that is the minimum average.
(60 + 64 + 75 + 71 + x)/5 = 70 ------> Multiply both sides by 5
(60 + 64 + 75 + 71 + x) = 350 -----> Combine like terms
270 + x = 350 -----> Subtract 270 from both sides
x = 80
Answer:
1000 runners
Step-by-step explanation:
Take total number of runners to be -----------x
90% of x managed to complete the marathon= 90/100 × x =0.9x
30% of those who completed the marathon were men= 30% × 0.9x
=0.3×0.9x= 0.27x
=270 men completed the marathon; this means
0.27x=270--------------------------------find x by dividing both sides by 0.27
x= 270/0.27
x=1000 runners
Answer:
(4x-3)(x+1)
Step-by-step explanation:
Answer:
B. Commutative
Step-by-step explanation:
He can do that because it's a sum
Answer:
It depends, Y or X have to be set up to get an actual number because you can simply plug any numbers.
