7 * 0.5 + 3 * 0.8 = 3.5 + 2.4 = 5.9
<span>5.9/10 X 100 = 59%
</span><span>59% concentration of new mixture</span>
Answer:
<u>D</u>
Step-by-step explanation:
The logical step is to <u>factorize the left side of the equation</u>, which becomes:
Then, you can take the square root on both sides.
Not asked, but good to understand the procedure regardless.