Questions on Algebra: Divisibility and Prime Numbers answered by real tutors!

Tutors Answer Your Questions about Divisibility and Prime Numbers (FREE)

Question 311682: Which of the following numbers disproves the statement “ a number that is divisible by 3 and by 6 is also divisible by 9 “ ?
A 18 B 30 c 36 D 54 E 90

Click here to see answer by Alan3354(30993)

Question 311488: the sum of the integers t and w is 495 . the units digit of t is 0 . if t is divided by 10 , the result is equal to w . what is the value of t ?
A 40 B 45 C 245 D 250 e 450

Click here to see answer by ankor@dixie-net.com(15656)

Question 312186: what is the prime factorization of the number 10808
Click here to see answer by Fombitz(13828)

Question 312186: what is the prime factorization of the number 10808
Click here to see answer by JBarnum(2044)

Question 312468: I need the LCD for these fractions:2/5,7/33,6/55,2/15,1/15,1/11,3/33. I came up with 165 which seems too big.
I also need LCD for these fractions:4/32,14/176,3/32,1/11,16/176,3/32,1/11. I came up with 352 which also seems too big.
Thank you for your help,
Robin
rmw12161@hotmail.com
Click here to see answer by solver91311(16897)

Question 313366: A prime number is a positive integer greater than 1 divisible by only 1 and
itself. How many prime numbers are between 100 and 110?
(A) 1 (B) 2 (C) 3 (D) 4 (E) 5
Click here to see answer by Fombitz(13828)

Question 313595: When 12345678 is divided by 9, the remainder is?
(A) 0 (B) 1 (C) 3 (D) 5 (E) 7
Click here to see answer by stanbon(57361)

Question 314469: The sum of all of the integers from 1 to 30 is 465. The sum of all of the integers from 1 to 30 that are divisible by 3 is
(A) 135 (B) 155 (C) 156 (D) 165 (E) None of these

Click here to see answer by Edwin McCravy(8909)

Question 315149: {1, 2, 3, K175, 176, 177, 178}
How many numbers in the set above have 5 as a factor but do not have 10 as a factor?
(A) 1 (B) 3 (C) 4 (D) 17 (E) 18

Click here to see answer by Fombitz(13828)

Question 315457: How many prime numbers does Set S have? S = { 1, 24, 6, 7, 13, 161, 171 }
a 3 b 4 c 5 d 6 e 7

Click here to see answer by Fombitz(13828)

Question 316495: what are the numbers that 945 are divisible by

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Question 317488: What is the sum of the digits of the smallest positive integer that is divisible by 2, 3, 4, 6, and 7?
A)14 B)16 C)9 D)12 E)15
Click here to see answer by Edwin McCravy(8909)

Question 317488: What is the sum of the digits of the smallest positive integer that is divisible by 2, 3, 4, 6, and 7?
A)14 B)16 C)9 D)12 E)15
Click here to see answer by MathTherapy(1425)

Question 318431: help me solve 5(k-9)-(4k+8)=2
Click here to see answer by jim_thompson5910(28595)

Question 318431: help me solve 5(k-9)-(4k+8)=2
Click here to see answer by stanbon(57361)

Question 318589: Factor completely. If prime, say so.
a. 40x^3-64x^2y
b. 125r^3-8s^3

Click here to see answer by JBarnum(2044)

Question 318832: Factor completely. If prime, say so.
125r^3 -8s^3
Click here to see answer by excoastie725(4)

Question 319441: What is the sum of the prime factors of 30?
(A) 2
(B) 5
(C) 10
(D) 15

Click here to see answer by mananth(12270)

Question 321049: find two prime numbers that, if multiplied, would generate a 400-digit number
Click here to see answer by stanbon(57361)

Question 321071: The Environmental Protection Agency (EPA) requires that cities monitor over 80 contaminants in
their drinking water. Samples from the Lake Huron Water Treatment Plant gave the results shown here. Only the range is reported, not the mean (presumably the mean would be the midrange). For each substance, estimate the standard deviation σ by using the methods shown in Table 8.11in section 8.7.
(b) Why might an estimate of σ be helpful in planning future water sample testing?

Click here to see answer by stanbon(57361)

Question 321123: Factor completely. If prime, say so.
9x^2 - 30x + 25
Click here to see answer by ehollins1(8)

Question 321125: Factor completely. If prime, say so.
16u^4 - v^4
Click here to see answer by mananth(12270)

Question 321122: Factor completely. If prime, say so.
5c^2 + 2c - 3
Click here to see answer by mananth(12270)

Question 321199: A two-digit number is divisible by 8, 12 and 18. The number is between
(A) 10 and 19 (B) 20 and 39 (C) 40 and 59 (D) 60 and 79 (E) 80 and 99
Click here to see answer by checkley77(12569)

Question 321625: When a number is divided by 10, the remainder is 9. When it is divided by 100, the
remainder is 89. When it is divided by 1000, the remainder is 789. Which of the
following could be that number?
A) 2 987 B) 6 789 C) 2 189 D) 987 E) 1 000

Click here to see answer by mananth(12270)

Question 322386: Factor completely. If prime, say so.
13-14y + y^2
Click here to see answer by Fombitz(13828)

Question 322622: Patrick spent 4/9 of an hour (h) in the batting cages on Friday and 7/9 of an hour on Saturday. He wants to spend 2 h total on the weekend. How much time should he spend on Sunday to accomplish this goal?

Click here to see answer by mananth(12270)

Question 323564: I need help with it all what is the best way to learn this stuff i can not fail this year plz help me!!!
Click here to see answer by jim_thompson5910(28595)

Question 323567: what formula to use to find 2 prime numbers that, if multiplied, would generate a 400-digit number?
Click here to see answer by jim_thompson5910(28595)

Question 323391: find the lcd of the fractions
-5/48 , 3/14
Click here to see answer by Fombitz(13828)

Question 323386: find the lcd of the fractions

-5/48 , 3/14
Click here to see answer by Fombitz(13828)

Question 325107: The product of two numbers is 180. The LCM of the
two numbers is 60. What is the GCF of the numbers?
Explain how you know.
Please help!
Click here to see answer by jim_thompson5910(28595)

Question 327163: Can anyone please help me?
There is a number that has 2,5, and 8 as divisors. This number has exactly seven additional divisors. What is the number?
Thank you for your help:)
Click here to see answer by solver91311(16897)

Question 329355: solve
6x+z=6+y
8x-3y=6
6x-2y+4z=1

Click here to see answer by Fombitz(13828)

Question 330131: solve and check 1/2+4m=3m-5/2
Click here to see answer by privani(34)

Question 331036: what two prime numbers multiplied equal a 400 digit number?

Click here to see answer by Alan3354(30993)

Question 331153: Explain very briefly how you would check for divisibility by 45?
Click here to see answer by Edwin McCravy(8909)

Question 332239: factor 2x^2 -240x+5500
Click here to see answer by jim_thompson5910(28595)

Question 332430: What is 0.00283 in words?
Click here to see answer by Edwin McCravy(8909)

Question 332607: which of the following number is divisible by 2 and 5
2658
2555
3690
or 7215
Click here to see answer by solver91311(16897)

Question 333329: If the sum of the integers n and n + 1 is greater than 99 and less than 109, what is the only possible prime value of n?

Click here to see answer by mananth(12270)

Question 333347: How many integers greater than 20 and less than 30 are each the product of exactly two different numbers, both of which are prime?
(A) Zero
(B) One
(C) Two
(D) Three
(E) Four
Click here to see answer by Edwin McCravy(8909)

Question 334408: what is the smallest number by with each of the following numbers must be divided to obtain a perfect cube.81,128,135,192,704
Click here to see answer by Alan3354(30993)

Question 334650: Write the answer in lowest terms:
13/18 + 11/18 = 24/18 =?
Click here to see answer by rfer(12662)

Question 334783: is 252 a prime number?
Click here to see answer by benazir.sj@gmail.com(109)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440