Answer: equation
Reasoning: So an easy way to remember this is, an equation has an equals sign. So remember equal sounds like equation so that’s a way to know. And an expression doesn’t have an equals sign.
Let s = northbound train
Then
2s = southbound train
:
Distance = time * speed
4s + 4(2s) = 600
:
4s + 8s = 600
:
12s = 600
:
s = 600/12
:
s = 50 mph is the northbound train
Then
2(50) = 100 mph is the southbound train
:
:
Check:
4(50) + 4(100) = 600
I have no idea what that is but good luck
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