Divisibility

The  exercise appears under the Pre-algebra Math Mission. This exercise has an application that uses factors and multiples of two numbers to determine divisibility.

Types of Problems
There is one type of problem in this exercise:


 * 1) Find another number that divides in evenly: This problem states that some number is divisible by two other numbers. The student is asked to select which number from a list must also divide into the number.Div1.png

Strategies
Knowledge of the divisibility rules and prime factorization can assist with accuracy and efficiency on this exercise. Furthermore, LCM and GCF skills can increase efficiency even further.
 * 1) If one of the numbers provided is a factor of one of the other initial numbers, that is the answer.
 * 2) Generally the number tends to be one of the smaller in the list, but this is not always the case.
 * 3) If one can quickly determine which prime numbers are factors of the given number this can lead to the correct answer since these numbers would also have to be factors of the answer.
 * 4) LCM and GCF skills, although not necessary, improve efficiency on this

Real-life Applications

 * 1) Divisibility leads to many number theoretic concepts (such as primality) which can be used for encryption and other computer science applications.