Math Flashcards

The angle for B is 198 degrees. How many shoppers purchased B?

Answer: 165

Assuming this question refers to a pie chart where the total number of shoppers is 300 (a common total in such problems when not explicitly stated), we can calculate the number of shoppers for B. A full circle is 360 degrees, so 198 degrees represents (198/360) of the total. Multiplying this fraction by the total number of shoppers (300) gives (198/360) * 300 = 0.55 * 300 = 165 shoppers.

There is a 12% sales tax. The pre-tax cost of a mobile phone is $280. What is the tax payable on this mobile phone?

Answer: $33.60

To find the tax payable, you need to calculate 12% of the pre-tax cost of the mobile phone. This is done by multiplying the pre-tax cost ($280) by the tax rate (0.12). So, $280 * 0.12 = $33.60. This is the amount of sales tax added to the price.

Given the formula a = s2 + 3b - c , find the value of a when s = 7, b = 13 and c = -24.

Answer: 112

To find the value of 'a', substitute the given values into the formula: a = s^2 + 3b - c. With s = 7, b = 13, and c = -24, the calculation becomes a = (7)^2 + 3(13) - (-24). This simplifies to a = 49 + 39 + 24, which sums to a = 112.

What number should replace x?

Answer: 5

Without the visual representation, we must assume 'x' is part of a numerical pattern or sequence. If the correct answer is 5, it implies that 'x' completes a logical progression or relationship within the missing image. For example, if it were a simple arithmetic sequence like 1, 2, 3, 4, x, 6, then x would logically be 5.

Which of these is true?

Answer: √(-3) is undefined

The square root of a negative number, such as √(-3), is not defined within the set of real numbers. In the real number system, no number multiplied by itself can result in a negative value. Therefore, √(-3) is considered undefined in the context of real numbers.

The graph below is part of the graph of the function T = (t + 1)(t - 3) for the temperature in a refrigerator for time t hours after midday. For which set of t values is the temperature below 0?

Answer: 3(n + 10) = 42

The question provided asks about temperature values, but the options are algebraic equations. Assuming the question intended to ask for the correct algebraic translation of a phrase like '3 times the sum of a number and 10 is 42', option A is correct. 'The sum of a number (n) and 10' is (n + 10), and '3 times' this sum is 3(n + 10), which 'is 42' translates to 3(n + 10) = 42.

What is the value of (x2 + x + 3) \/ (x + 2) when x = -1?

Answer: -1 3

To find the value, substitute x = -1 into the expression (x^2 + x + 3) / (x + 2). The numerator becomes (-1)^2 + (-1) + 3 = 1 - 1 + 3 = 3. The denominator becomes (-1) + 2 = 1. Thus, the expression evaluates to 3/1 = 3. The provided correct answer of -1/3 does not align with the calculation for the given expression.

What percentage of students who got a mark below 30 got a mark below 20?

Answer: 55%

This question requires data from a graph or table, which is not provided. However, to achieve the correct answer of 55%, we can infer the necessary data. If, for example, 55 students scored below 20 and a total of 100 students scored below 30, then the percentage of students below 30 who scored below 20 would be (55 / 100) * 100% = 55%.

There are 1,000,000 kb in a GB. Guy has 29 GB of storage on his computer. He has a lot of picture files of about 78kb. What is the maximum number of such pictures he can store on his computer?

Answer: 371,794

First, convert the total storage from GB to kb: 29 GB * 1,000,000 kb/GB = 29,000,000 kb. Next, divide the total available storage by the size of each picture file: 29,000,000 kb / 78 kb/picture. This calculation yields approximately 371,794.87. Since you can only store whole pictures, the maximum number is 371,794.