Dorris's average mark out of 3 tests was 82.
Her last mark was 3/2 times her first mark. The middle mark was 86.
What was the difference between her 1st and last mark?
+9481 Let's call the first test score a, second test score b, and third test score c.
(a + b + c) / 3 = 82
c = 3/2 * a = 3a/2
b = 86
Substitute the values we know for b and c into the first equation.
(a + 86 + 3a/2) / 3 = 82
Solve for a.
a + 86 + 3a/2 = 82 * 3
a + 3a/2 = 246 - 86
2a/2 + 3a/2 = 160
5a/2 = 160
a = 160 * 2/5 = 64
Substitute the value we found for a into the second equation to find c.
c = 3(64)/2 = 96
a - c = 64 - 96 = -32
...so her score improved 32 points from her first test to her last test!
If yall kept it simpler it would be simpler and SAT/GRE would be kaboom
but ok
Let f: first score
Q states that: f+3/2f+86=3 times average=3(82)=246
5/2f=246-86
5f=320
f=64
Let l: last score
l=3/2f=64.(3/2)=96
diff=96-64=32
if yall need to slow it down to really pedantic slowness go widda next answ
+9481 Let's call the first test score a, second test score b, and third test score c.
(a + b + c) / 3 = 82
c = 3/2 * a = 3a/2
b = 86
Substitute the values we know for b and c into the first equation.
(a + 86 + 3a/2) / 3 = 82
Solve for a.
a + 86 + 3a/2 = 82 * 3
a + 3a/2 = 246 - 86
2a/2 + 3a/2 = 160
5a/2 = 160
a = 160 * 2/5 = 64
Substitute the value we found for a into the second equation to find c.
c = 3(64)/2 = 96
a - c = 64 - 96 = -32
...so her score improved 32 points from her first test to her last test!
+130020
Calm down ,guest......we appreciate your answer, but there may be several ways to solve the same thing......just because you think that your answer is superior may not make it so.....
Hectictar's answer isn't any more "pedantic" than any other one........
Please dont be preposterously presumptuous: you really do not know what's in my mind. It's very offensive indeed when you contend vigorously that I believe my answer is better (I totally don't) and when you then decide to tell me to calm down. H's answer is completely fine. I will help out elsewhere where how we did things 55 years ago (i.e. very quickly, in our heads, with the correct answer, cross-checked and assuredly) isn't deprecated. Bye, Felicia.
+2539 Please dont be preposterously presumptuous: you really do not know what's in my mind. It's very offensive indeed when you contend vigorously that I believe my answer is better âŚ
Oh, my . . . This is great! We need another old gasbag! A companion for the forumâs Banker âone who articulates more, but is even less intelligible.
This one couches his precipitated blarney in unintelligible, self-absorbed self-important egotisms, presented in glorious century-old syntax, with missing apostrophes, commas, and periods, as a true testament to his âcross-checkingâ skills). He's hip, though, he ends his archaic writing with a modern meme: âBye, Felicia.â (A farewell to someone considered insignificant.)
Like the banker, he is not a âhas been,â rather heâs a ânever wereâ member in a group of wannabes â mathematicians, probably. Heâs practiced indignant criticism all of his life because itâs the only way he can create a contrast to measure his milestones of achievement.
I hope he stays around. We stylish, superior trolls really relish rare, refined dinning of preposterously presumptuous pretentious phrases in our smorgasbord. We also like to listen to the villains in the old Scooby-do cartoons while we enjoy our meal.
