This equation is incomplete: 1 2 3 4 5 6 7 8 9 = 100

One way to make it accurate is by adding seven plus and minus signs, like so.

1 + 2 + 3 – 4 + 5 + 6 + 78 + 9 = 100

How can you do it using only 3 plus or minus signs?

Using all the digits from 1 to 7, what two numbers have the largest product? For example, 1234 x 567 = 699678 but you can do much better than that.

Rearrange the letters of the first word to form a new one, then rearrange the letters of the new word to form a third.

ASLEEP _ _ _ _ _ _ _ _ _ _ _ _
PARTS _ _ _ _ _ _ _ _ _ _
IDEALS _ _ _ _ _ _ _ _ _ _ _ _

A man is looking at a picture on the wall and says, “Brothers and sisters I have none, but this man’s father is my father’s son.”

What is their relationship?

A boat has a ladder that has six rungs. Each rung is one foot apart. The bottom rung is one foot from the water. The tide rises at 12 inches every 15 minutes. High tide peaks in one hour.

When the tide is at its highest, how many rungs are under water?

What is special about 3,661 seconds past midnight on January 1, 2001?

Rhonda will go see ballet but not the opera. Her favorite number is eight and she doesn’t like nine. She likes salmon but not trout. She hates Mondays and likes Wednesdays. Does she use a comb or a brush?