Problems of the Week - November 8 to November 14

Rewards for Problems of the week:

5 stars for the correct answer at your level; 10 stars for the next level; 20 stars for 2+ levels up.

 Lower Elementary:

 Question: Abigail has 75¢ in coins. She has 1 quarter, 2 dimes, and the rest are nickels. How many nickels does Abigail have?

Upper Elementary: 

Question: The Lakeside Elementary School Choir is hosting a fund-raising concert event. They sold child tickets for $10 each and adult tickets for $20 each. They made $2,000. If they sold 60 adult tickets, how many child tickets did they sell?

Middle School:

Question: What number(s) between 250 and 275 is divisible by 2, 3, and 9?

Algebra and Up:

Question: What is the equation of a line perpendicular to y = –²/₃x + 3 and goes through the point (1, 3)? Give your answer in slope-intercept form.

Challenge problem to take home. 5 stars for the correct answer. 

What is the least number of guards needed to completely guard this art gallery?

The guards cannot move, and every part of the gallery must be in the line of sight of at least one guard.