let's start by approximating... as if someone said you have 3 seconds to solve... Decrease 2/3rds by 4/9ths. 4/9ths is roughly 1/2. I cut a pie into thirds and ate 1/3rd. Then I have 2/3rds left. If I decrease by appox 1/2 then only approx 1/3rd will be left. FORMALLY==> Divide 2/3 by 4/9 = (2/3)/(4/9) fraction rule #7: invert and multiply (2/3) × (9/4) = 18/12ths... oops.... that's no where near 1/3 revise thinking (converting words to equation.) s/b: (2/3) × (4/9) = 8/27 is 8/27 ~= 1/3 8/27 = 0.296 1/3 = 0.333 so yes ✔️✔️✔️ but..BUT... taking away 4/9th leaves 5/9ths in place so 2/3 × 5/9 = 10/27ths
that's what I was thinking too, 2/3 x 5/9 which is 10/27. 10/27 is more than two thirds. 4/9 = 44.4444%, 2/3 = 66.6666%, and since 44% is less than 50%, the answer should be slightly more than 1/3. So 10/27 checks out. then i realized it said substract
So if you where to say “decreased to” instead of “decreased by” then you would probably multiply, treating the 4/9ths as a ratio…like 4/9ths of 2/3rds…right? Idk when semantics factored into math problems but I don’t like it lol
Thanks again john 👍 you are awesome teacher
I totally agree!!
This is tricky. I took it as decreased by 4/9ths OF 2/3rds. So, I did x= 2/3 - (2/3 x 4/9).
13/25.09 yielding approx
thank u
let's start by approximating... as if someone said you have 3 seconds to solve... Decrease 2/3rds by 4/9ths. 4/9ths is roughly 1/2. I cut a pie into thirds and ate 1/3rd. Then I have 2/3rds left. If I decrease by appox 1/2 then only approx 1/3rd will be left.
FORMALLY==>
Divide 2/3
by
4/9
=
(2/3)/(4/9)
fraction rule #7:
invert and multiply
(2/3) × (9/4)
= 18/12ths...
oops.... that's no where near 1/3
revise thinking (converting words to equation.)
s/b:
(2/3) × (4/9)
= 8/27
is 8/27 ~= 1/3
8/27 = 0.296
1/3 = 0.333
so yes ✔️✔️✔️
but..BUT... taking away 4/9th leaves 5/9ths in place
so
2/3 × 5/9 = 10/27ths
that's what I was thinking too, 2/3 x 5/9
which is 10/27. 10/27 is more than two thirds. 4/9 = 44.4444%, 2/3 = 66.6666%, and since 44% is less than 50%, the answer should be slightly more than 1/3. So 10/27 checks out.
then i realized it said substract
The answer is 2/9.
Two ninths.
So if you where to say “decreased to” instead of “decreased by” then you would probably multiply, treating the 4/9ths as a ratio…like 4/9ths of 2/3rds…right? Idk when semantics factored into math problems but I don’t like it lol
3/9
2/9
Hi hello 👋👋