It should be " b "
That should be right but u may want to wait for others to respond to this to make sure
Answer:
k=2.1
Step-by-step explanation:
7/10k=21
x7 x7 Multiply seven from each side of the equation.
10k=21
/10 /10 Divide ten from each side of the equation. 21/10=2.1
k=2.1
That's a 33% increase.
I calculated this using the formula:

Where n = the new value (16 in your question), o = the old value (12 in your question) and the result is outputted as a percent increase. You can check that this is correct by finding 33% of 12, adding the result to 12, and checking that the result equals your "new" number.
Note that 33% is only an approximation as your question requires a number rounded to the nearest whole.
Answer:
No student liked only Nokia
Step-by-step explanation:
The information can be illustrated as shown on the Venn diagram.
The number of students who liked only Nokia is x.
The sum of all regions in the Venn diagram should be 40.
We add all to get:




Therefore no one liked only Nokia