Question #1:
To find the percentage of boy's in the class, divide.
9 / 36 = 0.25
0.25 * 100% = 25% (boys in the class)
We can write this proportion as 9/36 since this is the same as 25%.
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Question #2:
We know that the ear buds in both options cost $125.
The earbuds online are on a 20% discount.
The earbuds in store are on a 90$ sale
Lets find the discount for the online pair.
20% = 0.2
125 * 0.2 = 25
125 - 25 = $100 (price after discount)
After solving we can see that the earbuds in store are a better price. So, you will purchase the ear buds in store.
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Best Regards,
Wolfyy :)