HESI: Math

Question 1

integers

Answer 1

the set of whole (+) and (-) #s, INCLUDING 0.

-do not include fractions, decimals, or mixed numbers

Question 2

prime number

Answer 2

a whole # greater than 1 that has only 2 factors (itself & 1)
-meaning, a number that can be divided evenly only by 1 and itself

Question 3

composite number

Answer 3

a whole # greater than 1 that has more than 2 different factors

• meaning, any whole # that’s NOT a prime number
  ex) composite number 8 has the factors (1,2,4,8)

Question 4

even number

Answer 4

any integer that can be divided by 2 w/o leaving a remainder

ex) 2, 4, 6, 8, etc

Question 5

odd number

Answer 5

any integer that cannot be divided evenly by 2

ex) 3, 5, 7, 9, etc

Question 6

decimal number

Answer 6

a number that uses a decimal point to show the part of the number thats less than 1
ex) 1.234

Question 7

decimal point

Answer 7

a symbol used to separate the ones place from the tenths place in decimals or dollars from cents in currency

Question 8

decimal place

Answer 8

the position of a number to the R of the decimal point

IN the decimal 0.123:

• the 1 is in the 1st place to the R of the decimal point, indicating tenths place
• the 2 is in the 2nd place, indicating hundredths
• the 3 is in the 3rd place, indicating thousandths

Question 9

decimal (base 10, system)

Answer 9

number system that uses 10 diff digits (0-9)
-an example of a number system that uses something other than 10 digits is the binary or base 2, number system, used by computers (only uses numbers 0 & 1)

Question 10

write 0.24 as a fraction

Answer 10

24/100 = 6/25

Question 11

write the place value of each digit:

14, 059. 826

Answer 11

1; ten thousands
4; thousands
0; hundreds
5; tens
9; ones
8; tenths
2; hundredths 
6; thousandths

Question 12

write each decimal in words:
A. 0.06
B. 0.6
C. 6.0
D. 0.009
E. 0.113
F. 0.901

Answer 12

A. 0.06 (six hundredths)
B. 0.6 (six tenths)
C. 6.0 (six)
D. 0.009 (nine thousandths)
E. 0.113 (one hundred thirteen thousandths)
F. 0.901 (nine hundred one thousandths)

Question 13

factors (of a given #)

Answer 13

all of the #s that can be divided evenly into the given #

ex) 12 has six factors: 1, 2, 3, 4, 6, 12

Question 14

prime number

Answer 14

has only 2 (1 & itself)

Question 15

common factor

Answer 15

a factor that is shared by 2+ different #s

• the factors of 12 are (1, 2, 3, 4, 6, 12)
• the factors of 15 are (1, 3, 5, 15).
• The common factor of 12 & 15 = 1 & 3

Question 16

prime factor

Answer 16

a factor that is also a prime number

• prime factors of 12: (2, 3)
• prime factors of 15: (3, 5)

Question 17

multiple (of a given #)

Answer 17

a multiple (of a given #) is a # that can be obtained by multiplying that given # by a (+) integer

• multiples of 3: (3, 6, 9, 12, 15)
• multiples of 7: (7, 14, 21, 28, 35)

Question 18

prime factorization

Answer 18

-refers to the process of recording all prime factors of a given #.
-prime factorization is used to find quantities such as the LCM and the GCF
(A factor is recorded as many times as it is used)

• prime factorization of 60: (2 x 2 x 3 x 5)
• prime factorization of 72: (2 x 2 x 2 x 3 x 3)

Question 19

greatest common factor (GCF)

Answer 19

GCF of 2 #s is the largest # that is a factor of BOTH numbers

1. refer to the prime factorization of 60 & 72
   - prime factorization of 60: (2 x 2 x 3 x 5)
   - prime factorization of 72: (2 x 2 x 2 x 3 x 3)
2. to find the GCF of 60 & 72: find which #s appear in both prime factorizations
   - GCF of 60 & 72: (2 x 2 x 3 = 12)

Question 20

least common multiple (LCM)

Answer 20

LCM of 2 numbers is the smallest number thats a multiple of both numbers

1. refer to the prime factorization of 60 & 72
   - prime factorization of 60: (2 x 2 x 3 x 5)
   - prime factorization of 72: (2 x 2 x 2 x 3 x 3)
2. to find the LCM of 60 & 72: find which #s appear in both prime factorizations
   - LCM of 60 & 72: (2 x 2 x 3) x (2 x 3 x 5) = 12 x 30 = 360

Question 21

GCF & LCM rules

Answer 21

For 2 numbers a & b where (a < b):

• GCF of a & b must be LESS than or equal to a
• LCM of a & b must be GREATER than or equal to b