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OlgaM077 [116]
3 years ago
14

Mr Yang’s son has a total of twenty-one $1 and $2 coins in his money box. When he counts his money, he finds that its total valu

e is $30. How many coins of each type does he have?
Mathematics
1 answer:
irina [24]3 years ago
3 0

Hello!

To solve this, first assume all the coins are $1. Then, find the value that would have. 1 * 21 = $21.

Now, see how far away from $30 we are. 30 - 21 = 9. Therefore, we need an increase by $9.

For each coin changed from a $1 to a $2, how much of an increase is there? $1. Therefore, change 9 coins to $2 coins to have an increase of $9. If he has 9 $2 coins, he'll have 21 - 9 $1 coins, or 12.

Therefore, your final answer is 12 $1 coins and 9 $2 coins.

Hope this helps!

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Answer:

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Answer:

Becky needs approximately 3 containers to fil the vase up to 75%.

Step-by-step explanation:

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4 years ago
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Answer:

4 \times 3^{3}\\\\4\times3 \times3\times3\\\\108

Step-by-step explanation:

Four times three cubed

Given the statement, times means multiplication.

four times three

4        x         3

It says three cubed, where cubed means raised to 3. So that means we right an exponent, and the exponent is 3.

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When we have an exponent, that tells you how many times you will multiply it by itself. So since the exponent is 3, we multiply 3 by itself 3 times.

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So 4 x 3³ = 4 x 3 x 3 x 3

Lastly, if we get the product your result will be 108.

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