6th Grade Math Textbook, Progress

Logic: Conjunctions and Disjunctions

In logic, two statements can be combined to form a

compound statement using and, or a compound statement

using or.

It is raining andI am leaving. It is raining orI am leaving.

A compound statement using andis called a conjunction.

It is true only when bothoriginal statements are true.

A right angle measures 90
 and a straight angle measures 180
. True

A compound statement using oris called a disjunction.

It is true when bothof the original statements are true

or when oneof the original statements is true.

A rhombus has 4 sides or a square has 4 sides. True

Eleven is a prime number or eleven is a composite number. True

A rectangle is a space figure or a prism is a plane figure. False

Write a conjunction statement and a disjunction statement

for each exercise. Then tell whether each is TrueorFalse.

0 1. A robin is a bird. 0 2. A boat can float.

1. A dime is worth exactly 5¢. 01. A plane can fly.

0 3. Eighteen is a prime number. 0 4. 144  12  12

1. One is a composite number. 01. 56  5  280

0 5. 2400  80  2320 0 6. (173)  4  5

1. 75  69  6 01. 147  58  83

True True

True

True

False

True

False

False

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