Answer:
a)148.47
b)148.34
Step-by-step explanation:
Let π(x) be the prime-counting function that gives the number of primes less than or equal to x, for any real number x. For example, π(7) = 4 because there are four prime numbers (2, 3, 5, 7) less than or equal to 7.
We can see that π(7)=π(10) because there are four prime numbers (2,3,5,7) less than or equal to 10.
A good aproximation for π(x) is x / log x, where log x is the natural logarithm of x.
a)The number of primes between 1 and 1030.
1030/log(1030)=148.47
b) The number of primes between 1 and 1029.
1029/log(1029)=148.34
Extra: π(1029)=π(1030) because 1030 is not a prime.
Here is the equation: x+(x+20) = 120
Since you can't combine anything yet, its x+x+20=120
You need to get x by itself
Minus 20 from both sides
Its x+x=100 now
Combine the x's which is now 2x
Now divide 100 by 2 which is 50
x=50
---------------
Lets check:
50+(50+20)=120
Now combine the numbers in the parentheses
Its now 50+70=120
50+70=120 and 70-50=20
As you can see, he ran 50 minutes the first day and 70 minutes the second day
1. The correct statement is the first one, which is: <span>Add the two equations, solve for y, and then substitute –1 for y to find x.
</span>
2. Therefore, you have the following system of equations:
<span>
4x+8y=20
-4x+2y= -30
3. When you a</span>dd the two equations, and clear the variable "y", you obtain:
10y=-10
y=-1
4. Now, you must substitute -1 for y (y=-1) to find x, as below:
4x+8y=20
4x+8(-1)=20
4x-8=20
4x=20+8
4x=28
x=28/4
x=7
Assuming they are dice, to work out the probability that the product is 8, the dice either have to be 2 and 4 or 4 and 2. The blue dice therefore has to be a 2 (4 is not less than 3), which is a 1 in 6 probability. The yellow one therefore has to be 4, which again is 1 in 6. The probablility that these both happen at the same time is given when they are multiplied together.

x

=

.
Hope that is useful.
Answer:
B. rectangle
Step-by-step explanation:
it will be a rectangle with the dimension of diameter and height of the cylinder