Answer:
56
Step-by-step explanation:
Answer:
ya queritway te daiys deoxre huisdjkgkek vviddigikekwk dfjf
The answer is <span>b.3x + 15 = 55 - x
</span>
x - Jill's present age
y - dad's present age
<span>In 5 years, Dad will be three times as old as his daughter Jill will be then:
y + 5 = 3(x + 5)
</span><span>The sum of their present ages is 50:
x + y = 50
We have the system of two equations now:
</span>y + 5 = 3(x + 5)
x + y = 50
Let's rearrange the second equation:
If: x + y = 50
Then: y = 50 - x
Now, substitute y from the second equation (y = 50 - x) into the first one:
y + 5 = 3(x + 5)
50 - x + 5 = 3(x + 5)
50 + 5 - x = 3*x + 3*5
55 - x = 3x + 15
Rearrange it a bit:
3x + 15 = 55 - x
Therefore, the correct choice is b.
Answer:
Step-by-step explanation:
Let us assume that if possible in the group of 101, each had a different number of friends. Then the no of friends 101 persons have 0,1,2,....100 only since number of friends are integers and non negative.
Say P has 100 friends then P has all other persons as friends. In this case, there cannot be any one who has 0 friend. So a contradiction. Hence proved
Part ii: EVen if instead of 101, say n people are there same proof follows as
if different number of friends then they would be 0,1,2...n-1
If one person has n-1 friends then there cannot be any one who does not have any friend.
Thus same proof follows.
