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:
3
Step-by-step explanation:
I think you misses attaching the photo, so please have a look at my photo for your better understanding.
We know the formula for rate of change of the parabola line:
Given here:
a= 2 => f(a) = 2
b=6 => f(b) = 2
Substitute all the values into the function, we have:
So the rate of change is 3
Answer:
The number of red pens is 20.
The number of blue pens is 4.
Step-by-step explanation:
We are given that, the ratio of number of red pens to the number of blue pens is 5 : 1.
∴ Let us assume that the number of red pens be 5<em>x</em> and number of blue pens be <em>x</em>.
Total number of pens in the desk drawer = 24
Now, according to question :
Number of red pens + Number of blue pens = 24
⇒5<em>x</em> + <em>x</em> = 24
⇒6<em>x</em> = 24
⇒
So, number of red pens in the drawer = 5<em>x</em> = 5 × 4 = 20
Number of blue pens in the drawer = <em>x</em> = 4