g>one factor (itself), whereas primes must have exactly two.","points":1},{"id":"1b353ac5-d736-473c-a60b-3cf464252cae","cardType":"basic","front":"Distinguish between a factor and a multiple.","back":"

A factor divides into a number exactly (no remainder).
A multiple is in the number's times table.

","points":2},{"id":"76d2eb5c-f042-487d-8e8c-c24a6e72cc9a","cardType":"basic","front":"What is the Highest Common Factor (HCF)?","back":"The biggest number that divides exactly into all given numbers.","points":1},{"id":"575225b9-54d5-4360-bd3e-6c371fb1ad22","cardType":"basic","front":"How do you find the HCF using prime factorisations?","back":"

Identify the prime factors shared by all numbers.
Multiply the smallest power of each shared prime.

","points":2},{"id":"3c4fd048-966b-4b6d-8d53-41f9c8148d71","cardType":"basic","front":"What is the Lowest Common Multiple (LCM)?","back":"The smallest positive number that is a multiple of all given numbers.","points":1},{"id":"6b0466f2-7bd4-48a6-8d5e-b4c18c2190c8","cardType":"basic","front":"How do you find the LCM using prime factorisations?","back":"

Identify every prime factor that appears in any of the numbers.
Multiply the largest power of each of those primes.

","points":2},{"id":"9ccb3686-8302-4aa3-8aa9-63cae9fea3a5","cardType":"basic","front":"When solving problems about buses or alarms repeating at different intervals, which mathematical value is required?","back":"The Lowest Common Multiple (LCM) of the intervals.","points":1},{"id":"435b78e3-acc6-4520-996e-de8d6d24e0b9","cardType":"basic","front":"Find the HCF of $2^4 \times 3$ and $2^3 \times 3^2$.","back":"$$2^3 \times 3 = 24$","points":2},{"id":"7c4fbd30-a7df-46ba-8fc6-3369d3d507e3","cardType":"basic","front":"Find the LCM of $2^3$ and $2^2 \times 3$.","back":"$$2^3 \times 3 = 24$","points":2},{"id":"e70646cf-af2d-425e-af33-914c60e2eca3","cardType":"basic","front":"What does it mean for two numbers to be coprime?","back":"Their Highest Common Factor (HCF) is 1.","points":1},{"id":"117bdf4d-9c79-4adc-84e9-53c28159c4be","cardType":"basic","front":"When given the HCF and LCM and asked to find the original numbers, what is the first step?","back":"Divide the LCM by the HCF.","points":1},{"id":"de89dbaf-87ad-4743-89a7-a7b09e158ea2","cardType":"basic","front":"Why is multiplying the original numbers together often an incorrect way to find the LCM?","back":"It produces a common multiple, but it is only the lowest if the numbers share no common factors.","points":2},{"id":"2fcd9513-b2fa-4cc4-ba77-026bd024e5fe","cardType":"basic","front":"Find the HCF of $A = 2^2 \times 5$ and $B = 2^3 \times 3$.","back":"$$2^2 = 4$","points":2}]}],"examCountdown":null,"formulaUrl":null,"intro":"$L3c","title":"Prime Factors, HCF and LCM Flashcards","topicSidebar":"$L3d"}]}],"topicId":"48b9c267-1c46-44c1-bc13-f93d8ca74edc","walled":"$L3e"}],"$L3f"]