Correct Answer: D

Rationale: To calculate the total bill after adding a 20% tip, you need to find 120% of the original bill. This is because adding a 20% tip means paying 120% of the bill. So, $48.30 120/100 = $57.96. Therefore, the correct answer is $57.96. Choice A ($9.66) is incorrect as it represents only the 20% tip amount. Choice B ($38.64) is incorrect as it is the original bill amount without the tip. Choice C ($48.30) is incorrect as it is the original bill amount and does not include the additional 20% tip.

Correct Answer: B

Rationale: Using PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction): (3/2)(8/3) · (5/4) = (24/6) · (5/4) = (4/1) · (5/4). To divide fractions, the second fraction is flipped and then multiplied by the first fraction, resulting in (4/1)(4/5) = (16/5), which simplifies to 3(1/5) or 2.

Correct Answer: A

Rationale: To calculate the decline in business, start with the 40% decline in the 70% share of print subscriptions: 40% of 70% = 0.40 0.70 = 0.28 = 28% decline. Next, calculate the growth from the 60% increase in the 25% share of online subscriptions: 60% of 25% = 0.60 0.25 = 0.15 = 15% growth. To find the overall change, sum the decline and growth percentages: 28% decline + 15% growth = -0.28 + 0.15 = -0.13 = 13% decline. Therefore, the overall percentage change in the newspaper's business is a 13% decline. Option A is the correct answer. Option B is incorrect because it doesn't consider the correct calculations for both the decline and growth. Option C is incorrect as it misinterprets the net change in business. Option D is incorrect as it miscalculates the overall percentage growth or decline.

Correct Answer: A

Rationale: To find the discount amount, calculate 20% of $30: 0.20 $30 = $6. Subtract the discount from the original price to get the sale price: $30 - $6 = $24. Therefore, the correct answer is $24. Choices B, C, and D are incorrect as they do not reflect the correct calculation of applying a 20% discount to the original price of $30.

Correct Answer: B

Rationale: To find the area of a triangle, you use the formula A = 1/2 base height. Substituting the given values: A = 1/2 10 cm 7 cm = 35 cm². Therefore, the correct answer is B. Choice A (70 cm²) is incorrect as it seems to be the product of the base and height rather than the area formula. Choice C (140 cm²) is incorrect as it appears to be twice the correct answer, possibly a result of a miscalculation. Choice D (100 cm²) is incorrect as it does not reflect the correct calculation based on the given base and height values.