Algebraic Expressions & Equations
Ms. Cross leads The National Math Club at the middle school where she teaches. At the first club meeting of the school year, 60% of the students in attendance were boys. If there was one fewer girl than boy in attendance, how many students attended the first club meeting?
International Left Handers Day is celebrated each year in August. If the ratio of the number of days of the month before International Left Handers Day to the number of days of the month after it is 2:3, on what date in August is this special day observed?
What is the 20th term of the arithmetic sequence 13, 19, 25, 31, ...?
The common difference is 19 – 13 = 6. Now that we know that we can find the 20th term by 13 + 6(20 – 1). Thus, the 20th term is 127.
What is the sum of A and B in the arithmetic sequence 7, 15, 23, A, 39, B, ...?
Summer Fun Camp enrollment costs 85 dollars each week per camper. Each camper may register for up to three of the optional workshops offered for an additional charge of $5.50 a week per workshop, or 15 dollars per week for three workshops. The total charge for Chloe’s enrollment to attend Summer Fun Camp for n weeks this summer is 768 dollars. If Chloe has registered to participate in two workshops each week, what is the value of n?
A construction crew places orange barrels on both sides of a particular road to indicate a work zone. On each side of the road, the distance between the centers of consecutive barrels is 15 feet. If this work zone is 1.5 miles long, what is the total number of barrels that will be used?
Fiona has two part-time jobs during her summer vacation. She works part-time as a counselor at a local day camp, and she has another part-time job as a life-guard at the community swimming pool. Fiona works a combined total of 40 hours every week between the two jobs.
The first week working both jobs it rained all but one day, so three-fourths of the hours she worked that week were at the day camp. How many hours did Fiona work at the pool the first week?
Archer has three sons named Tanner, Carver and Decker. Archer’s age is three times the sum of Carver’s and Decker’s ages. The sum of Tanner’s and Carver’s ages is half Archer’s age. If Tanner’s age is three times Carver’s age, what is the ratio of the ages of Carver and Decker? Express your answer as a common fraction.
Derrick received a total of 21 gift cards for graduation. He received gift cards in each of four denominations, $25, $50, $75 and $100. The number of $100 gift cards Derrick got was twice the number of $75 gift cards he received. The total value of the $50 gift cards he got exceeded the total combined value of the $25, $75 and $100 gift cards by $100. How many $25 gift cards did Derrick get for graduation?
Last week the National Competition concluded, and Luke Robitaille from Texas became the first ever two-time MATHCOUNTS National Champion. Let’s look at some of the problems he had to solve on the way to the top!
On Sunday, May 13th, 224 middle-school math students participated in the written rounds of the 2018 Raytheon MATHCOUNTS National Competition. On Monday, May 14th, the top 12 competitors will go head to head in the National Countdown Round to determine the 2018 MATHCOUNTS National Champion. Let’s solve a few problems from the 2017 National Countdown Round.