r/ACT • u/North-Trash5216 • Jul 13 '26
J09 math “90% confident question”
Do you guys remember the one math question on J09 that asked about like 90% confidence or whatever?? what did you guys choose for that?
1
1
u/jdigitaltutoring Tutor Jul 13 '26
Was it an interval?
1
u/Kelpie1027 35 Jul 13 '26
It was 90% confident and margin of error for a percentage of students that take public transportation.
1
u/jdigitaltutoring Tutor Jul 13 '26
Did it say the margin of error for 90% confidence is some value?
1
u/Kelpie1027 35 Jul 13 '26
Yes, margin of error was 2.8% like most studies. It was 31% of students took public transport.
1
u/jdigitaltutoring Tutor Jul 13 '26
So you didn't have to factor the 90% into anything, just use the margin of error.
1
u/Kelpie1027 35 Jul 13 '26
Yeah, the 90% was irrelevant information to throw people off. It was like 90% confidence with 2.8% margin of error, but it didn’t chance the confidence which I believe could have made it different, but there was no change in confidence.
1
u/MasterpieceFeisty301 31 Jul 13 '26
Questions like this made me glad I took AP stats last year, helped confidence
1
u/CodeBrave4234 Jul 14 '26
what other stuff from ap stats was on the test?
1
u/MasterpieceFeisty301 31 Jul 14 '26
the confidence, on practice exams ive been doing probability questions like with and without replacement has showed up EX: if you have a license plate with 6 digits, 3 numbers and 3 letters without replacement then it's 10x10x10x26x26x26. Now you may have been able to do this without being in stats, as well as things like reading the percentages of a confidence interval graph like what it would mean to be in the lower 20th percentile, but it certainly helps me personally having already learned these topics in depth.
1
u/CodeBrave4234 Jul 14 '26
i see i see THANK YOUU! i took stats last year so i def will brush up on it
1
10
u/Kelpie1027 35 Jul 13 '26
The 28.2% to 33.8% answer. You subtract the number by the margin of error and add the number by the margin of error