Answer:
B) 47.5%
Step-by-step explanation:
Refer to the normal distribution chart attached. If 130 is 2 standard deviations higher than the mean (ignore the numbers beneath the percentages), then by the empirical rule, this means that 34%+13.5%=47.5% of adults are between IQs of 100 and 130. Therefore, option B is correct.
10. Infinitely many solutions:
Simplify this equation:
When the equation becomes
This equality is true for all x, thus the equation has infinitely many solutions.
11. The equation should have one solution x=-1.
First, simplify the equation:
This equation will have solution x=-1 when
Therefore, the initial equation is
12. The equation should have infinitely many solutions.
Simplify it:
When this equation will have infinitely many solutions.