How many numbers within 150 are the product of three prime numbers

How many numbers within 150 are the product of three prime numbers

2×3× 5\7\… \There are seven starting with 23 2x3
There are three starting with 2x5x 7 / 11 / 13 2x5
2x7x (none)
There is one starting with 3x5x7 and 3x5
7 + 3 + 1 = 11
A: there are 11 numbers in 150 that are the product of three prime numbers

There are () numbers within 150, which are the product of three different prime numbers

Prime number: 2 3 5 7 11 13 17 19 23 29
2*3*5=30；2*3*7=42；2*3*11=66；2*3*13=78；2*3*17=102；2*3*19=114；2*3*23=138;
2*3*29=174>150
2*5*7=70;2*5*11=110;2*5*13=130;2*5*17=170>150
3*5*7=105;3*5*11=165>150
5*7*11=385>150
So there are only 11 groups
There are (11) numbers within 150 which are the product of three different prime numbers

What are the numbers with 6 divisors within 100?

Because this number has six divisors, because: 6 = (1 + 1) × (2 + 1) or 6 = 5 + 1, the number within 100 can be: 25 = 32, 2 × 32 = 18, 2 × 52 = 50, 2 × 72 = 98, 3 × 22 = 12, 3 × 52 = 75, 5 × 22 = 20, 5 × 32 = 45, 7 × 22 = 28, 7 × 32 = 63, 11 × 22 = 44, 1

If K, regardless of its value, x = - 1 and X is the solution of the equation [KX + a] / 2 = [- x-bk] / 3, find the value of ab

Substituting x = - 1 into the original equation
(-k+a)/2=(1-bk)/3
3(-k+a)=2(1-bk)
-3k+3a=2-2bk
-3k+3a=-2bk+2
The equation holds for any value of K
Then - 3 = - 2b
3a=2
The solution is a = 2 / 3, B = 3 / 2

What is the distance from the point on the number axis representing − 12 to the origin______ ．

|0-12 | = 12

The workers built a 960 meter highway. Three eighths of the total length was built on the first day, and 40% of the total length was built on the second day. How many meters more was built on the second day than on the first day?

960 * 40% - 960 * 3 / 8
=384—360
=24 meters
A: the second day was 24 meters more than the first
If you have any new questions, please don't send them in the form of follow-up questions. Please send me another question and ask me for help,

How to do multiplication and division of rational numbers
(- 7) * 3 / 10 + (- 3 / 10)

（-7）*3/10+(-3/10)=-7* 3/10 - 3/10=-7* 3/10 - 3/10*1=（-7-1）*3/10=-8*3/10=-12/5

How about half plus six, one plus 12, one plus 20, one plus 30, one plus 42/

Half plus six, one plus 12, one plus 20, one plus 30, one plus 42
=1-1 / 2 + 1 / 2-1 / 3 + 1 / 3-1 / 4 + 1 / 4-1 / 5 + 1 / 5-1 / 6 + 1 / 6-1 / 7 (split term cancellation)
=1-1/7
6/7

If inequality (A-3) x

(a-3)x3

The inner diameter of stainless steel coil is 300 mm, the width is 40 mm, the weight is 60 kg, and the density is 7.75?

Let the inner diameter be r = 300 mm, the outer diameter be r, the volume of the inner diameter be V1 = 3.14 * 300 * 300 * 40, V2 = 3.14 * r * r * 40, M1 = 7.75 * V1, M2 = 7.75 * V2, m1-m2 = 60 kg, the solution is: r = (the unit is not unified, I don't know what state your 7.75 is)