Answer:
C
Step-by-step explanation:
Answer:
x= - 9/28 ± √60/7
Step-by-step explanation:
The <em>echo</em> number 20222022202220222022 is the <em>perfect</em> square of 4496890281.
<h3>What echo number is a perfect square</h3>
An <em>echo</em> number has a <em>perfect</em> square if its square root is also a <em>natural</em> number. After some iterations we found that <em>echo</em> number 20222022202220222022 is a <em>perfect</em> square:

The <em>echo</em> number 20222022202220222022 is the <em>perfect</em> square of 4496890281. 
To learn more on natural numbers, we kindly invite to check this verified question: brainly.com/question/17429689
If you want to easily find the solution you can use your calculator.
Just divide 77 by 110 and see the result.
77/110 = 0.7 = 7/10 = 70/100 = 70%
100% - 70% = 30%
Explanation
110*x=77
x=77/110, but the answer is not a percent
So 77/110 = ?/100 => ?=77*100/110=70 => 70%
But since 70% does not represent a percentage decreasement, we need to subtract it from the 100%
100% - 70% = 30%