I think the mean of variable a is 4
Let m and j be the current ages of Matthew and Jenny, respectively.
Now, Matthew is 3 times as old as Jenny, so the variables are in the following relation:

In 7 years, both of them will be 7 years older, i.e. their ages will be m+7 and j+7, and Matthew will be twice as old:

Now, remembering that m=3j, we can rewrite the second equation as

So, Jenny is 7 and Matthew is 21 (he's 3 times older).
In fact, in 7 years, they will be 14 and 28, and Matthew will be twice as old.
Answer:
2300
Step-by-step explanation:
We are given that
Out of 200 , four ducks are tagged.
We have to find the number of ducks in the preserve if 46 ducks are tagged.
Let x be the number of ducks in the preserve.
If number of tagged ducks increases then number of preserved ducks also increases.It is in direct proportion.
According to question



x=2300
Answer:
3. Speed is based on a specific direction
Step-by-step explanation:
Generally, speed is a scalar quantity equal to the magnitude of velocity. Velocity is a vector quantity that is speed together with a specific direction.
The answer choice that seems most in agreement with this description seems to be ...
3. Speed is based on a specific direction