Adding 25 and 47 gives a total of 72. This is a straightforward addition problem.

Dividing both the numerator and the denominator by 4 simplifies 4/8 to 1/2. This is the most reduced form of the fraction.

0.75 is equivalent to 75/100, which simplifies to 3/4. This conversion demonstrates the relationship between decimals and fractions.

The number 11 has exactly two distinct positive divisors: 1 and 11. This meets the definition of a prime number.

15% of 100 is calculated by multiplying 100 by 0.15, which results in 15. This is a fundamental percentage calculation.

First, distribute 3 across (2x + 4) to get 6x + 12, then subtract 5x to combine like terms, resulting in x + 12. This tests the application of the distributive property and simplifying expressions.

Subtracting 5 from both sides gives 2x = 12, and dividing both sides by 2 results in x = 6. This is a basic linear equation solution.

The area of a rectangle is calculated by multiplying its length by its width: 8 cm x 5 cm equals 40 cm². This applies a fundamental geometric formula.

A fair coin has two equally likely outcomes, making the probability of landing heads 1 out of 2, or 1/2. This illustrates a basic concept in probability.

Dividing 0.2 by 0.5 results in 0.4, as 0.2/0.5 equals 2/5, which is 0.4. This problem reinforces decimal division concepts.

The decimal 0.6 can be expressed as 6/10, which simplifies to 3/5. This conversion demonstrates understanding of equivalent fractions.

Calculating 25% of $80 results in a discount of $20 (0.25 x 80 = 20). This is a typical problem involving percentage discounts.

The common factors of 18 and 24 include 1, 2, 3, and 6, with 6 being the largest. This problem involves finding the greatest common divisor.

Dividing both sides of 3(x - 2) = 12 by 3 yields x - 2 = 4, so adding 2 gives x = 6. This tests basic algebraic manipulation and the distributive property.

5% of 200 is calculated by multiplying 200 by 0.05, which equals 10. This is a basic percentage calculation relevant to everyday contexts.

Distribute and simplify both sides: 2x + 6 = 3x - 3 + 1 simplifies to 2x + 6 = 3x - 2. Subtracting 2x from both sides and then adding 2 yields x = 8.

The ratio 2:3:4 sums to 9 parts, and the total of the angles in any triangle is 180°. Multiplying 180 by 4/9 gives 80°, which is the largest angle.

Multiply both sides of the equation by the reciprocal of 3/4, which is 4/3, resulting in x = 9 × (4/3) = 12. This is a straightforward application of inverse operations.

A 30% markup increases the price, but a subsequent 30% discount is taken from the increased price, resulting in a final price that is lower than the original. The percentages do not cancel each other out because they are applied in sequence.

Following the order of operations, first evaluate the parentheses: 2 - 4 = -2. Then, multiply by 3 to get -6, and finally, compute 7 - (-6) + 2^3, which simplifies to 7 + 6 + 8 = 21.