QR Challenge: Inequalities Word Problems

Created using the ClassTools QR Treasure Hunt Generator

Teacher Notes

A. Prior to the lesson:

1. Arrange students into groups. Each group needs at least ONE person who has a mobile device.

2. If their phone camera doesn't automatically detect and decode QR codes, ask students to

• Download a QR reader (e.g. I-Nigma | NeoReader | Kaywa) onto their mobile devices
• Bring these devices into the lesson.

3. Print out the QR codes.

4. Cut them out and place them around your class / school.

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B. The lesson:

1. Give each group a clipboard and a piece of paper so they can write down the decoded questions and their answers to them.

2. Explain to the students that the codes are hidden around the school. Each team will get ONE point for each question they correctly decode and copy down onto their sheet, and a further TWO points if they can then provide the correct answer and write this down underneath the question.

3. Away they go! The winner is the first team to return with the most correct answers in the time available. This could be within a lesson, or during a lunchbreak, or even over several days!

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C. TIPS / OTHER IDEAS

4. A detailed case study in how to set up a successful QR Scavenger Hunt using this tool can be found here.

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Questions / Answers (teacher reference)

Question	Answer
1. After selling a dozen copies of the Daily Bulletin, a newsdealer had fewer than 75 copies left. How many copies did the newsdealer have originally?	less than 87 copies
2. A house and lot together cost more than $89,000. The house costs $1000 more than seven times the cost of the lot. How much does the lot cost?	more than $11,000
3. Martha wants to rent a car for a week and pay no more than $130. How far can she drive if the car rental costs $94 a week plus $0.12 a mile?	300mi or less
4. Jordan's salary is $1250 a month plus a 5% commission on all his sales. What must the amount of his sales be to earn at least $1500 each month?	$5000 or more
5. The sum of two consecutive integers is less than 55. Find the pair of integers with the greatest sum.	26 and 27
6. The sum of two consecutive even integers is at most 400. Find the pair of integers with the greatest sum.	198 and 200
7. Two trucks start from the same point at the same time and go in opposite directions. One truck travels at 88km/h and the other travels at 72km/h. How long must they travel to be at least 672km apart?	at least 4.2h
8. Between them, Terry and Shelley have 50 cassettes. If Shelley has more than two thirds as many cassettes as Terry, at least how many cassettes does Shelley have? At most how many does Terry have?	Shelley has at least 21 and Terry has at most 29
9. A bag contains 100 marbles, some red and the rest blue. If there are no more than one and a half times as many red marbles as blues ones in the bag, at most how many red marbles are in the bag? At least how many blues ones are in the bag?	at most 60 red marbles and at least 40 blues marbles
10. Ken has 22 coins, some of which are dimes and the rest are quarters. Altogether, the coins are worth more than $3.40. At least how many of the coins are quarters? At most how many are dimes?	at least 9 quarters and at most 13 dimes
11. The length of a rectangle is 4cm longer than the width and the perimeter is at least 48cm. What are the smallest possible dimensions for the rectangle?	10cmx14cm
12. A pair of consecutive integers has the property that 7 times the smaller is less than 6 times the greater. What are the greatest such numbers?	5 and 6
13. At 1PM two trains traveling toward each other leave from towns that are 312km apart. One train averages at most 82km/h and the other at most 74km/h. What is the earliest possible time for them to meet?	3PM
14. If Maura were able to increase her average cycling speed by 3.5km/h, she would be able to cover in 2h a distance at least as great as that which now takes 3h. What is her best average speed at present?	7km/h
15. There are three exams in a marking period. A student received grades of 75 and 81 on the first two exams. What grade must the student earn on the last exam to get an average of no less than 80 for the marking period?	84
16. Betty earns a salary of $14,000 per year plus 8% commission on all her sales. How much must her sales be if he annual income is to be no less than $15,600?	at least $20,000
17. A mechanic earns $20 an hour, but 25% of his earnings are deducted for taxes and various types of insurance. What is the least number of hours the mechanic must work in order to have no less than $450 in after-tax income?	30h
18. At least how many grams of copper must be alloyed with 387g of pure silver to produce an alloy that is no more than 90% pure silver?	43g
19. The length of a rectangle exceeds the width by 10cm. If each dimension were increased by 3cm, the area would be no less than 111cm^2 more. What are the least possible dimensions of the rectangle?	12cmx22cm

 

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