Q&A - Chapter 2 Flashcards
Q: What are the key goals when working with numbers in pharmacy?
Add, subtract, multiply, and divide whole numbers.
Add, subtract, multiply, and divide fractions, reduce them to the lowest terms, and discuss mixed numbers.
Add, subtract, multiply, and divide decimals, and round them to specific place values.
Convert between fractions, decimals, and percentages.
Express numbers in ratios and proportions, and solve for unknowns.
Visual Example: A flowchart showing whole numbers → fractions → decimals → percentages with arrows between them.
Q: What does “complex fraction” mean?
A: It’s a fraction where either the numerator, the denominator, or both are fractional units themselves.
Visual Example: A fraction like (1/2) / (3/4) with labels showing how both parts are fractions.
Q: What does “convert” mean in math?
A: It means changing something from one form to another, like turning a fraction into a decimal or a percentage.
Visual Example: A number like 1/2 being transformed into 0.5 and then 50% with arrows connecting them.
Q: What’s a decimal?
A: It’s a fraction with a denominator that’s a power of 10, written with numbers to the right of a decimal point.
Visual Example: A number like 0.75 shown as 3/4 with the decimal point highlighted.
Q: What are decimal places?
A: They are the positions of numbers to the right of the decimal point, like tenths, hundredths, and thousandths.
Visual Example: A number like 3.141 with labels for the tenths, hundredths, and thousandths places.
Q: What’s the denominator in a fraction?
A: It’s the bottom part of the fraction that shows how many equal parts make up the whole.
Visual Example: A fraction like 3/4 with the “4” labeled as the denominator.
Q: What does “improper fraction” mean?
A: It’s a fraction where the numerator is equal to or greater than the denominator, like 5/3.
Visual Example: A fraction like 7/4 highlighted with the numerator larger than the denominator.
Q: Why do we find the least common denominator?
A: It’s the smallest number that all the denominators in a problem can divide evenly into, helping with adding and subtracting fractions.
Visual Example: Fractions like 1/4 and 1/6 being rewritten as 3/12 and 2/12 with a shared denominator.
Q: Why do we use a leading zero?
A: It’s a zero before the decimal point in numbers less than 1, like 0.5, to reduce mistakes in dosing.
Visual Example: A number like “.5” crossed out and replaced with “0.5” to emphasize safety.
Q: What’s a mixed number?
A: It’s a number that combines a whole number and a fraction, like 2 1/2.
Visual Example: A picture of 2 1/2 with the whole number and fraction labeled separately.
Q: What does “invert” mean in fractions?
A: It means flipping the numerator and denominator, like turning 2/3 into 3/2.
Visual Example: An arrow flipping a fraction like 4/5 into 5/4.
Q: What is the numerator?
A: It’s the top number in a fraction that shows how many parts you have.
Visual Example: A fraction like 3/4 with the “3” labeled as the numerator.
Q: What does “percent” represent?
A: It shows a portion out of 100 parts, like 50% means 50 out of 100.
Visual Example: A pie chart split into 100 parts, with 50 shaded to represent 50%.
Q: What does “product” mean in math?
A: It’s the result of multiplying two numbers together.
Visual Example: A simple multiplication problem: 3 × 4 = 12, where 12 is the product.
Q: What is a proper fraction?
A: It’s a fraction where the numerator (top number) is smaller than the denominator (bottom number), like 3/4.
Visual Example: A pizza with 3 out of 4 slices shaded, showing the fraction 3/4.
Q: What does “proportion” mean?
A: It shows the relationship between parts, often using ratios like 1:2.
Visual Example: A scale with two sides: one holding 1 apple and the other holding 2 apples, labeled as 1:2.
Q: What is the quotient in division?
A: It’s the answer to a division problem. For example, in 10 ÷ 2 = 5, the quotient is 5.
Visual Example: A division problem written out, with the quotient highlighted.
Q: What does “ratio” mean?
A: It’s a way of comparing two numbers, like 1:2 means for every 1 of something, there are 2 of something else.
Visual Example: Two jars, one with 1 marble and the other with 2 marbles, labeled as a 1:2 ratio.
Q: What is the remainder in division?
A: It’s the amount left over after dividing a number. For example, in 10 ÷ 3 = 3 R1, the remainder is 1.
Visual Example: A visual of 10 blocks divided into groups of 3, with 1 block left over.
Q: What does “round” mean in math?
A: It means adjusting a number to its nearest place value, like rounding 3.56 to 3.6.
Visual Example: A number line showing 3.56 rounded to 3.6.
Q: What is a scored tablet?
A: It’s a tablet with an indentation, making it easy to break into equal parts.
Visual Example: A picture of a round tablet with a clear line down the middle.
Q: What’s wrong with trailing zeros like “1.0”?
A: A trailing zero can be mistaken for a bigger number, like “10.” Writing 1 is safer.
Visual Example: A pill bottle labeled “1 mg” with “1.0 mg” crossed out.
Q: What is a whole number?
A: It’s a number with no fractions or decimals, like 1, 2, 3, and so on.
Visual Example: A group of apples labeled as 1, 2, 3, without any fractions.
- Adding Multiple Numbers: 154 + 1,063 + 25 + 376
To add these numbers, start by lining them up vertically, aligning the digits by place value:
154
1,063
25
376
——
1,618
Step-by-step:
Add the digits in the ones place: 4 + 3 + 5 + 6 = 18 (write 8, carry 1).
Add the digits in the tens place: 5 + 6 + 2 + 7 = 20, plus the carried-over 1 = 21 (write 1, carry 2).
Add the digits in the hundreds place: 1 + 0 + 0 + 3 = 4, plus the carried-over 2 = 6.
Add the thousands place: 1 (from 1,063).
Final answer: 1,618
- Subtracting Two Numbers: 163 - 69
When subtracting, align the digits and subtract column by column:
163
- 69
——
94
Step-by-step:
Start with the ones place: 3 - 9. Since 3 is smaller, borrow 1 from the tens place, making it 13 - 9 = 4.
Move to the tens place: After borrowing, it’s 5 - 6. Borrow again from the hundreds place to make it 15 - 6 = 9.
The hundreds place now has nothing left, so it’s 0.
Final answer: 94
- Multiplying Whole Numbers: 256 × 43
To multiply these numbers, use long multiplication:
256
× 43
——
768 (256 × 3)
+ 10240 (256 × 40)
——
11008
Step-by-step:
Multiply 256 by 3 to get 768.
Multiply 256 by 40 (4 × 10) to get 10,240.
Add the results: 768 + 10,240 = 11,008.
Final answer: 11,008
- Dividing Whole Numbers: 256 ÷ 16
To divide, determine how many times 16 fits into 256:
Step-by-step:
Start with the first digit of 256 (2). Since 16 is larger than 2, consider the first two digits (25).
16 fits into 25 once, so write 1 above the line and subtract: 25 - 16 = 9.
Bring down the next digit (6), making it 96.
16 fits into 96 exactly 6 times: 96 ÷ 16 = 6.
Final answer: 16
- Adding Decimals: 25.6 + 456 + 35.67
Align the decimal points before adding:
25.60
456.00
+ 35.67
———
517.27
Step-by-step:
Line up the decimal points and add zeros to fill in any blanks.
Add the numbers column by column, starting with the hundredths place: 0 + 0 + 7 = 7.
Move to the tenths place: 6 + 0 + 6 = 12 (write 2, carry 1).
Continue with the ones, tens, and hundreds places: Add each column as usual.
Final answer: 517.27
- Subtracting Decimals: 354.29 - 45.390
Align the decimal points and subtract:
354.290
- 45.390
———
308.900
Step-by-step:
Align the decimals and add trailing zeros to ensure equal places.
Subtract each column, borrowing as necessary.
Keep the decimal point aligned in the answer.
Final answer: 308.90
- Multiplying Decimals: 12.56 × 65.031
First, multiply as if the decimals are not there:
1256
× 65031
——–
1256 (1256 × 1)
37680 (1256 × 3)
628000 (1256 × 5)
8124000 (1256 × 6)
——–
81647936
Step-by-step:
Multiply the numbers as whole numbers to get 81647936.
Count the total decimal places in the original numbers (2 in 12.56 and 3 in 65.031, so 5 total).
Place the decimal point 5 places from the right: 816.47936
Final answer: 816.48 (rounded to the nearest hundredth).
- Dividing Decimals: 655.08 ÷ 1.2
Move the decimal point in both numbers to make the divisor a whole number, then divide:
6550.8 ÷ 12
Step-by-step:
Move the decimal one place to the right in both numbers: 655.08 becomes 6550.8, and 1.2 becomes 12.
Divide as usual: 6550.8 ÷ 12 = 545.9
Final answer: 545.90
- Adding Fractions: 1/2 + 3/4 + 7/8
First, find a common denominator:
1/2 = 4/8
3/4 = 6/8
7/8 = 7/8
Step-by-step:
Convert all fractions to have a denominator of 8.
Add the numerators: 4 + 6 + 7 = 17.
The result is 17/8, which simplifies to 2 1/8.
Final answer: 2 1/8