Dosage Calculations Packet
Unit I – Basic Mathematics Review
This unit will review Arabic and Roman numerals,
fractions, decimals, percentage, and ratio and proportion.
ARABIC AND ROMAN NUMERALS
Arabic and Roman numerals are used interchangeably to
express quantity or degree of measure. Roman numbers are
formed by combining the following letters according to the
rules stated below:
Arabic numbers Roman numbers
½ ss
1 I
5 V
10 X
50 L
100 C
500 D
1000 M
1. To repeat a Roman number doubles its value. I =1; II=2
2. To place a letter to the right of a Roman number adds
its value to that number. V=5; VI=6.
3. To place a letter to the left of a Roman number
decreases the value of that number by the amount
of the number added. V=5; IV=4.
Practice Problems
Write the Arabic numbers for the following:
1. III
2. XVI
4. VI
5. CM
1
,3. XXXIX
6. XXIV
2
,Write the Roman numbers for the following:
7. 2
8. 14 9. 40 10. 69
11. 80 12.150 13. 99 14. 19
Answers:
1. 3 2. 16 3. 39 4. 6 5. 900 6. 24
7. II 8. XIV 9. XL 10. LXIX
11. LXXX 12. CL 13. IC 14. XIX
FRACTIONS
Definition: A fraction is a part of a whole number. A
fraction has 2 parts, the top number is called the numerator
and the bottom number is called the denominator.
Example: ½ = 1 is the numerator and 2 is the
denominator. There are 4 types of fractions:
1. Proper fractions – the numerator is less than the
denominator. Example: ½.
2. Improper fractions – the numerator is greater than the
denominator. Example: 6/5.
3. Complex fractions – the numerator or denominator may
be either a fraction or a whole number.
Example: ½ or ½
2 ¾
4. Mixed number – there is a whole number and a fraction
combined. Example: 3 ½.
3
, To change a mixed number to an improper fraction,
you must multiply the whole number by the
denominator and add the numerator. Example: 3 ½ =
7/2.
Practice Problems
Reduce the following fractions to the lowest terms
2/4= 10/20= 2/8 =
3/6= 15/20= 8/12=
3/9= 2/10= 5/10=
4/6= 3/12= 3/15=
Answers:
1. ½ 2. ½ 3. 1/4 4. ½ 5. ¾ 6. 2/3
7. 1/3 8. 1/5 9. ½ 10. 2/3 11. ¼ 12. 1/5
Change the following improper fractions to mixed numbers
1. 6/4= 2. 7/5= 3. 15/8=
6. 11/10=
4. 3/2= 5. 7/3=
Answers:
1. 1 ½ 2. 1 2/5 3. 1 7/8 4. 1 ½ 5. 2 1/3 6. 1 1/10
Change the following mixed numbers to improper fractions
1. 3 ½= 2. 6 ½=
4. 33 1/3=
4
Unit I – Basic Mathematics Review
This unit will review Arabic and Roman numerals,
fractions, decimals, percentage, and ratio and proportion.
ARABIC AND ROMAN NUMERALS
Arabic and Roman numerals are used interchangeably to
express quantity or degree of measure. Roman numbers are
formed by combining the following letters according to the
rules stated below:
Arabic numbers Roman numbers
½ ss
1 I
5 V
10 X
50 L
100 C
500 D
1000 M
1. To repeat a Roman number doubles its value. I =1; II=2
2. To place a letter to the right of a Roman number adds
its value to that number. V=5; VI=6.
3. To place a letter to the left of a Roman number
decreases the value of that number by the amount
of the number added. V=5; IV=4.
Practice Problems
Write the Arabic numbers for the following:
1. III
2. XVI
4. VI
5. CM
1
,3. XXXIX
6. XXIV
2
,Write the Roman numbers for the following:
7. 2
8. 14 9. 40 10. 69
11. 80 12.150 13. 99 14. 19
Answers:
1. 3 2. 16 3. 39 4. 6 5. 900 6. 24
7. II 8. XIV 9. XL 10. LXIX
11. LXXX 12. CL 13. IC 14. XIX
FRACTIONS
Definition: A fraction is a part of a whole number. A
fraction has 2 parts, the top number is called the numerator
and the bottom number is called the denominator.
Example: ½ = 1 is the numerator and 2 is the
denominator. There are 4 types of fractions:
1. Proper fractions – the numerator is less than the
denominator. Example: ½.
2. Improper fractions – the numerator is greater than the
denominator. Example: 6/5.
3. Complex fractions – the numerator or denominator may
be either a fraction or a whole number.
Example: ½ or ½
2 ¾
4. Mixed number – there is a whole number and a fraction
combined. Example: 3 ½.
3
, To change a mixed number to an improper fraction,
you must multiply the whole number by the
denominator and add the numerator. Example: 3 ½ =
7/2.
Practice Problems
Reduce the following fractions to the lowest terms
2/4= 10/20= 2/8 =
3/6= 15/20= 8/12=
3/9= 2/10= 5/10=
4/6= 3/12= 3/15=
Answers:
1. ½ 2. ½ 3. 1/4 4. ½ 5. ¾ 6. 2/3
7. 1/3 8. 1/5 9. ½ 10. 2/3 11. ¼ 12. 1/5
Change the following improper fractions to mixed numbers
1. 6/4= 2. 7/5= 3. 15/8=
6. 11/10=
4. 3/2= 5. 7/3=
Answers:
1. 1 ½ 2. 1 2/5 3. 1 7/8 4. 1 ½ 5. 2 1/3 6. 1 1/10
Change the following mixed numbers to improper fractions
1. 3 ½= 2. 6 ½=
4. 33 1/3=
4
