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A math teacher drove by a playground that was full of boys and dogs. The teacher happened to notice that there was a total of 40 heads and 100 feet. How many boys and how many dogs were there?

User Shastri
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2 Answers

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Final answer:

There are 30 boys and 10 dogs.

Step-by-step explanation:

Let's use a system of equations to solve this problem. Let's say that the number of boys is 'B' and the number of dogs is 'D'.



Each person has one head, so the total number of heads is B + D = 40.

Each person has two feet, so the total number of feet is 2B + 4D = 100.

Now, we can solve this system of equations to find the values of B and D.

From the first equation, we can solve for B: B = 40 - D.

Substitute this value into the second equation: 2(40 - D) + 4D = 100

Solve for D: 80 - 2D + 4D = 100, 2D = 20, D = 10.

Now substitute this value back into the first equation to solve for B: B = 40 - 10, B = 30.

Therefore, there are 30 boys and 10 dogs.

User Toinbis
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There were 30 boys and 10 dogs. 40 heads all together . Then each boy has 2 feet so thats 30*2 = 60 and each dog has 4 feet thats 10*4 = 40  60+40=100 feet
User Advanced Customer
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