<h3>
Answer: </h3><h3>
speed of train A = 44 mph</h3>
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Work Shown:
x = speed of train A
y = speed of train B
"train A travels 4/5 the speed of train B" (I'm assuming "train one" is supposed to read "train B"). So this means x = (4/5)y
distance = rate*time
d = x*7
d = (4/5)y*7 = (28/5)y represents the distance train A travels
d = y*7 = 7y represents the distance train B travels
summing those distances will give us 693
(28/5)y + 7y = 693
5*( (28/5)y + 7y ) = 5*693
28y + 35y = 3465
63y = 3465
y = 3465/63
y = 55
Train B's speed is 55 mph
4/5 of that is (4/5)y = (4/5)*55 = 4*11 = 44 mph
Train A's speed is 44 mph
D.4 he should apply 4 treatments to each of the groups
Answer:
b
Step-by-step explanation:
solve for c by simplifying both sides of the equation then isolate the variable
Answer:
325
Step-by-step explanation:
You must have heard about Arithmetic Progressions (AP)
Arithmetic progressions are a series of numbers such that every successive number is the sum of a constant number and the previous number.
Our very own counting numbers form AP
For example :-
2 = 1 + <u>1</u>
3 = 2 + <u>1</u>
4 = 3 + <u>1</u>
The number in bold (1) is that constant number which is added to a number to form its successive number.
To find the sum of series forming AP, we use the formula :-

here,
- n is the number of terms
- a is the first number of the series
- an is the last number of the series
So we'll use all this information to find the sum of continuous numbers from 1 to 25 where 1 is the first term(a) and 25 is the last(an).
and n is 25




So, the value of S comes out to be 325.
The reasonable estimate of 288 can be 300 because it's close to 300