The number of people who like only basketball is: 120 - 50 = 70.

The number of people who like only football is 120 - 40 = 80.

The number of people who like only football is 120 - 50 = 70.

The number of people who like at least one sport is: 120 + 80 - 50 = 150. Therefore, those who like neither is: 200 - 150 = 50.

The number of people who like only music is 80 - 50 = 30.

The number of people who like only rock music is 150 - 50 = 100.

Students who like only vanilla = Total vanilla - Both = 20 - 10 = 10.

The first term is 1, the second term is 1/2, and the third term can be calculated as 1/(1 + 1/2) = 2/3. The sum is 1 + 1/2 + 2/3 = 2.

The reciprocals are 1 and 2, which are in arithmetic progression with a common difference of 1/2.

The reciprocals are 1 and 2, which are in arithmetic progression. The third term's reciprocal is 3, so the third term is 1/3.

In a harmonic progression, the reciprocals of the terms form an arithmetic progression. The reciprocals of 2 and 3 are 1/2 and 1/3. The common difference is 1/3 - 1/2 = -1/6. The third term's reciprocal will be 1/3 - 1/6 = 1/6, so the third term is 6.

In a harmonic progression, the reciprocals of the terms form an arithmetic progression. The reciprocals of 2 and 4 are 1/2 and 1/4. The common difference is -1/4. Therefore, the third term's reciprocal is 1/4 - 1/4 = 0, which means the third term is 1.

In a harmonic progression, the reciprocals of the terms form an arithmetic progression. The reciprocals of the first two terms are 1/2 and 3/4. The common difference is 1/4, so the reciprocal of the third term is 1/2 + 1/4 = 3/4. Therefore, the third term is 1/(3/4) = 4/3.

The reciprocals of the terms are 1/3 and 1/6. The common difference is (1/6 - 1/3) = -1/6. The third term's reciprocal will be 1/6 - 1/6 = 0, which means the third term is 1/12, thus the answer is 12.

The reciprocals of the first two terms are 1/3 and 1/6. The common difference is 1/6 - 1/3 = -1/6, which is incorrect. The correct common difference is 1/3 - 1/6 = 1/6.

The reciprocals of 3 and 6 are 1/3 and 1/6, which are in arithmetic progression.

The reciprocals of the terms are 1/4 and 1/2. The common difference is 1/2 - 1/4 = 1/4.

The reciprocals are 1/4 and 1/8. The common difference is 1/8 - 1/4 = -1/8. The third term's reciprocal will be 1/8 - 1/8 = 0, hence the third term is 16.

The reciprocals are 1/4 and 1/8. The common difference is 1/8 - 1/4 = -1/8, which means the common difference of the corresponding arithmetic progression is 1/8.

The first term is 5, and the second term in the harmonic progression corresponds to the reciprocal of the second term in the arithmetic progression, which is 5 + 2 = 7. Thus, the second term is 1/7.

The reciprocals are 1/5 and 1/10. The common difference is 1/10 - 1/5 = -1/10, which is the difference in the arithmetic progression.

The reciprocals are 1/5 and 1/10. The common difference is -1/10. The reciprocal of the third term is 1/10 - 1/10 = 1/15, so the third term is 15.

The nth term of a harmonic progression can be expressed as 1/(1/a + (n-1)d) where d is the common difference of the corresponding arithmetic progression.

'1A' in hexadecimal is 1*16 + 10 = 26 in decimal.

In hexadecimal, 'A' represents 10 and '3' represents 3. Therefore, A3 = (10 * 16^1) + (3 * 16^0) = 160 + 3 = 163.

The number of books that are only fiction is calculated by subtracting the number of books that are both from the total fiction books: 50 - 10 = 40.

The equation of a line in slope-intercept form is y = mx + b, where m is the slope and b is the y-intercept. Here, m = 3 and b = -2, so the equation is y = 3x - 2.

The slope indicates the steepness of the line, representing the ratio of the rise over the run.

In logic, if 'P implies Q' is true, it means that whenever P is true, Q must also be true.

A premise is a statement or proposition that provides the basis for a conclusion in a logical argument.