Show:
Prime Factorizations
GCF
LCM
Word Problems!
Mystery Box
100
What is the "prime factorization" of a number?
The longest possible factor string for a number, made up of only prime numbers.
100
What is the greatest common factor of two numbers?
The greatest factor that two or more numbers share.
100
What is the least common multiple of two numbers?
The least multiple that two or more numbers share.
100
Mr. and Mrs. Smith have 9 children. Each of their children has 7 children of their own. How many great-grandchildren do Mr. and Mrs. Smith have?
Trick question - haha
100
A doctor gives you three pills and tells you to take one every half-hour. How long will they last?
1 hour
200
Why is the prime factorization the longest possible factor string for any whole number (including strings that have composite numbers)?
The prime factorization is the most you can break down, or decompose, any whole number.
200
What is the greatest common factor of 76 and 58?
2
200
What is the LCM of 25 and 26?
650
200
Mr. Weiler has 79 cookies. He wants to give the each of the 17 highest magazine sellers the same number of cookies for a snack. What is the greatest number of cookies he can give each student? How many will he have left over?
Each student will receive 4 cookies and he will have 11 left over to share with Ms. Parks
200
If you only had one match, and you entered a dark room that contained only three items, a kerosene lamp, an oil heater, and kindling wood, what would you light first?
The match
300
What is the prime factorization of 240?
2 x 2 x 2 x 2 x 3 x 5
300
How can you use the prime factorizations of two numbers to find their GCF?
To find the GCF of two numbers using their prime factorizations you make a factor tree to find the prime factorizations, circle the prime factors the two numbers have in common, and multiply the common prime factors to produce the GCF.
300
How can you use the prime factorizations of two numbers to find their LCM?
Make a factor tree to find the prime factorizations, circle their shared prime factors, list the shared prime factors (this is the GCF), then multiply by the remaining factors in each prime factorization.
300
Andre and Camila are comparing their special numbers. Andre's number has a prime factorization with six prime numbers. Camila's number has a prime factorization with only three numbers. Andre says this means his number is greater than Camila's. Camila says that is not necessarily true. Who is right?
Camila - what if Andre has the prime factorization 2 x 2 x 2 x 2 x 2 x 2 = 32 and Camila has the prime factorization 11 x 11 x 11 = 1331?
300
How many birthdays does the average man have?
one
400
What is the prime factorization of 3571?
3571
400
What is the GCF of 2520 and 2700?
180
400
What is the LCM of 170 and 187?
1870
400
Which of the numbers below is the product of exactly three different prime numbers? 15 20 30 57
30
400
Divide 30 by 1/2 and add 10. What's the answer?
70
500
What is the prime factorization of 3572?
2 x 2 x 19 x 47
500
What is the GCF of 2503 and 3049?
1
500
How do you know (without actually finding the LCM) when the least common multiple of two numbers will be less than their product?
When the numbers have a GCF that is greater than 1 (or when the numbers share a common factor other than 1).
500
Fred and Angelica work on weekends and holidays doing odd jobs around Tappan. They are paid by the day, not the hour. They each earn the same whole number of dollars per day. Last month Fred earned $184 and Angelica earned $207. How many days did each person work? What is their daily pay?
Their daily pay is $23. Fred worked 8 days and Angelica worked 9 days.
500
A man builds a house with 4 sides (so a rectangular building). Each side faces south. A bear walks by. What color is the bear?
White