Quiz 2.1

Is the collection well defined?

The collection of U.S. governors

• well-defined; not a set

• well-defined; is a set

• not well-defined; not a set

• not-well-defined; is a set

Write a word description for the set:

N = {9, 10, 11, 12, ...}

Write a word description for the set:

W = {Saturday, Sunday}

Express the set using the roster method.

The set of months of the year that have exactly 30 days.

• M = {September, October, November, December}

• M = {April, June, September, November}

• M = {January, February, March }

• M= { }

Express the set using the roster method.

G = {x|x is a lowercase letter of the alphabet that follows d and comes before j}

• G = {d,e,f,g,h,i j}

• G = {e,f,g,h}

• G = {e,f,g,h,i}

• G = {k,l,m,n,l,p,...,z}

• N = {0, 1, 2, 3}

• N = {1, 2, 3,...}

• N = {1, 2, 3}

• N = {1, 2, 3, 4}

• S = {15, 16, 17, ...,59}
• S = {15, 16, 17, ..., 60}
• S = {15, 60}
• S = {16, 17, 18, 19, ..., 50}

{x | x is living U.S. presidents born before 1960}

• Empty set

• Not Empty

Organize these options into the right categories.

Groups:

(a) Empty

,

(b) Not Empty

• {x | x is a natural number less than 7}

• {x | x is a pig that can fly}

• { 1, 2, 3,4}

• {Alabama, Tennessee, Georgia, Florida}

• { }

• {x | x is a day of the week that starts with P}

True or false:

3 ∈ {2, 4, 6, 8, 10}

• True

• False