The top 1/5 of the runners advance to the finals for the track and field competition. What is the decimal value of that number?
2 answers:
You might be interested in
Answer:
[a,b] divides n
Step-by-step explanation:
Let us denote the least common multiple of a and b [a,b]=m.
We want to prove that m divides n, where n is a multiple of a and b.
We suppose m does not divide n, then by the Division Theorem, there exists q and r integers such that:
(1) ... n=mq+r, where 0<r<m
As n is a multiple of a and b, there exists s and t integers such that:
sa=n and tb=n
Same thing happens to m as it is the least common multiple, there exists u and v such that:
ua=m and vb=m
So (1) has the following form:
n=mq+r ⇒ sa=uaq+r ⇒sa-uaq=r⇒(s-uq)a=r and
n=mq+r ⇒ tb=vbq+r ⇒ tb-vbq=r⇒ (t-vq)b=r
So r is a multiple of a and b, but r<m which is a contradiction as, m is the least common multiple of a and b. So this concludes the proof.
So this means that is and integer.
As m= vb, then is an integer, lets say
=v; and as m=ua, then
=u.
So v=
=a, so
divides a; on the other hand,
u=
=b, so
divides b. From this we can conclude that
is a common divisor of a and b.
Answer:
C
Step-by-step explanation:
Okay, the catch of this question is that they do a very good job of explaining Maria's age in terms of George's age, but they leave George's age in terms of Maria's all up to you.
First start off by doing an expression of what they explicitly give you. Maria's age in terms of George's age.
Let's use variables g, representing George's age and m representing Maria's age
m = 2g + 3
Okay, this is all dandy and all, but they ask us for George's age in terms of Maria's, so we need to isolate for g.
subtract the 3 from both sides, like so:
m - 3 = 2g
then divide 2 from both sides: (remember we're dividing the whole thing)
(m-3)/2 = g
Now we have an expression for George's age in terms of Maria's.
g = (m-3)/2 or
The answer that gives us this, is C.