Math Teasers are meant for thinking outside of the box. They require more logical thinking than being a math whiz-kid. Think creatively! Today we have an Algebraic Logic Puzzle called the Zoo Riddle.
At the zoo they are weighing the animals in groups.
Assign variables for each of the animals
e = elephant c = crocodile m = monkey
Rewrite the equations
e + 2c = 1200
2c + 4m = 400
e + 4m = 1000
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Subtract the second equation from the first equation:
e + 2c = 1200
–2c – 4m = –400
e – 4m = 800
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e – 4m = 800 Our new equation
e + 4m = 1000 The third line
2e = 1800 add them together
e = 900 pounds The elephant weighs 900 pounds
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Use the information we just learned and put it into the third line to find the weight of the monkey.
e + 4m = 1000
900 + 4m = 1000
4m = 100
m = 25 pounds Each monkey weighs 25 pounds
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Now we can use the weight of the elephant in the first equation to find the weight of the crocodiles.
e + 2c = 1200
900 + 2c = 1200
2c = 300
c = 150 pounds The crocodiles are 150 pounds each.
FINAL ANSWER: The elephant is 900 pounds; the crocodiles are 150 pounds each; and the monkeys are 25 pounds each.
These types of puzzles are known as algebraic logic puzzles or system of equations puzzles. They are excellent for worksheets because they teach algebraic thinking through visual or thematic elements.
Here are a few more puzzles following that exact structure, ranging in difficulty:
Find the weight of 1 Cow, 1 Pig, and 1 Sheep.
1 Cow + 2 Pigs = 900 lbs.
2 Pigs + 3 Sheep = 500 lbs.
1 Cow + 3 Sheep = 800 lbs.
Find the value of each fruit.
1 Pineapple + 2 Apples = $10
2 Apples + 3 Bananas = $11
1 Pineapple + 3 Bananas = $15
Find the weight of the Dog, Cat, and Rabbit.
Dog + Cat = 15 kg
Cat + Rabbit = 10 kg
Dog + Rabbit = 11 kg
Pro-Tip for solving: Add all three equations together to find the weight of 2 Dogs + 2 Cats + 2 Rabbits, then divide by two!
Determine the total cost of the final line.
2 Backpacks + 1 Ruler = $55
1 Backpack + 3 Rulers = $40
3 Backpacks + 2 Rulers = ?
Are you ready to challenge your math mind? Sign up for class(es) at MyTutorLesson – Math. We work with students from elementary school through the beginning of college.
