Answer:
35
Step-by-step explanation:
We know the factors of Lena's age are 2 and 5. The least common multiple must have these factors and the factors of 14, so will at least have factors of 2, 5, and 7.
Apparently, the dad's age is 5·7 = 35.
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The GCF is 5; the LCM is 70 = 5×14.
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Sometimes, I use a little 3-part diagram to think about LCM and GCF. Here, it would look like ...
(2 [5) 7]
where the numbers in curved brackets (2·5) and the numbers in square brackets [5·7] are factors of the two numbers of concern (Lena's age, her dad's age). The middle number in both brackets [5) is the greatest common factor, and the product of all three numbers is their least common multiple.
Here, the product of outside numbers, 2·7 = 14, represents the ratio of the LCM to the GCF. We know that Lena's age has factors of only 2 and 5, so the numbers in the diagram have to be (2[5)7], where 2 and 7 are on the ends and 5 is in the middle.
Using arithmetic and the information provided, there were 6 persons at the party.
<h3>Number of people at the party</h3>
The question is asking us to use the cost of the plates served to each person to calculate the number of people in the party from the information available in the question.
- Normal charge of a plate of food = $95
- Additional charge on each plate of food = $12.75
- Total cost of the party = $656
- Total cost of food for each person = $95 + $12.75 = $107.75
Number of people at the party can be obtained from; Total cost of food at the party/ Total cost of each plate of food
= $656/ $107.75 = 6 persons
Learn more about arithmetic: brainly.com/question/2171130
Answer:
D
Step-by-step explanation:
3*(-7)=(-21)