LANTITE Numeracy flashcards
LANTITE Numeracy · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Order of operations
- Evaluate brackets first, then indices, then multiplication and division from left to right, then addition and subtraction from left to right.
- Percentage increase
- To increase an amount by p%, multiply it by (1 + p/100); for example, a 15% increase multiplies by 1.15.
- Percentage change formula
- Percentage change equals the new value minus the old value, divided by the old value, then multiplied by 100.
- Fraction of an amount
- Multiply the amount by the fraction: a/b of N equals (a/b) × N; for example, 2/5 of 30 is 12.
- Dividing by a fraction
- Multiply by the reciprocal: dividing by a/b is the same as multiplying by b/a.
- Ratio sharing
- For ratio a:b, total parts equal a + b; each share is its part divided by total parts, multiplied by the total amount.
- Direct proportion
- Two quantities are directly proportional when one is a constant multiple of the other; doubling one quantity doubles the other.
- Inverse proportion
- Two quantities are inversely proportional when their product is constant; doubling one quantity halves the other quantity.
- Solving linear equations
- Perform the same operation on both sides to isolate the variable, then check the answer by substitution.
- Negative exponent rule
- A negative exponent means reciprocal: a to the power of minus n equals 1 divided by a to the power n, for a not zero.
- Rounding decision rule
- Identify the required place value and look at the next digit; if it is 5 or more, round up, otherwise keep the digit.
- Metric length conversions
- One kilometre equals 1000 metres, one metre equals 100 centimetres, and one centimetre equals 10 millimetres.
- Area of rectangle
- Area equals length multiplied by width; the result is expressed in square units such as square metres.
- Area of triangle
- Area equals one half multiplied by base multiplied by perpendicular height; the height must be perpendicular to the chosen base.
- Circumference of circle
- Circumference equals two times pi times the radius, or pi times the diameter; use pi approximately equal to 3.14.
- Area of circle
- Area equals pi multiplied by the radius squared; square the radius before multiplying by pi.
- Volume of prism
- Volume equals the area of the uniform cross-section multiplied by the length or height of the prism.
- Pythagoras theorem
- In a right-angled triangle, the square of the hypotenuse equals the sum of the squares of the other two sides.
- Angle sum triangle
- The three interior angles of any triangle add to 180 degrees; angles on a straight line also add to 180 degrees.
- Similar figure scale factors
- If corresponding lengths scale by factor k, areas scale by k squared and volumes scale by k cubed.
- Speed formula
- Speed equals distance divided by time; rearrange to distance equals speed times time or time equals distance divided by speed.
- Hectare conversion
- One hectare equals 10,000 square metres, which is the area of a square 100 metres by 100 metres.
- Mean calculation
- Add all values and divide by the number of values; the mean is affected by extreme values in the data.
- Median calculation
- Order the values from smallest to largest and choose the middle one; with an even count, average the two middle values.
- Mode
- The mode is the value that occurs most often in a data set; a data set may have no mode or several modes.
- Range
- Range equals the largest value minus the smallest value and measures the spread of the data.
- Probability scale
- Probability ranges from 0 for impossible events to 1 for certain events; all probabilities lie between these values.
- Complementary probability
- The probability that an event does not occur equals 1 minus the probability that it does occur.
- Independent events rule
- For independent events, multiply their probabilities to find the probability that both occur; coin tosses are independent.
- Relative frequency
- Relative frequency equals the number of times an event occurs divided by the total number of trials.
- Pie chart sector angle
- A sector angle equals the category frequency divided by the total frequency, multiplied by 360 degrees.
- Interquartile range
- The interquartile range equals the upper quartile minus the lower quartile and describes the spread of the middle half.