When you divide a fraction by a fraction, you're really just multiplying by a reciprocal. A reciprocal is the fraction flipped around.
So, 1/8 <span>÷ 1/4 is the same thing as 1/8 x 4/1
Now, you just multiply. 1 times 4 is 4. 8 times 1 is 8.
1/8 x 4/1=4/8
4/8 simplified is 1/2
So that is how 1/8</span><span>÷1/4=1/2</span>
Step-by-step explanation:
the introduction of a fraction tells us that we are dealing with multiplications, and therefore a geometric sequence (where every new term is created by multiplying the previous term by a constant factor, the ratio r).
I think your teacher made a mistake, or you made one when typing the question in here.
there is no factor r that creates
15×r = 9
and
9×r = 5/27
it would mean that
15 × r² = 5/27
r² = 5/27 / 15 = 5/27 × 1/15 = 5/405 = 1/81
r = 1/9
but 15 × 1/9 = 5 × 1/3 = 5/3 is NOT 9
and 9 × 1/9 = 9/9 = 1 is NOT 5/27
so, this can't be right.
on the other hand
15 × r = 9
r = 9/15 = 3/5
and then
9 × 3/5 = 27/5
so, either the sequence should have been
15, 5/3, 5/27
or (and I suspect this to be true)
15, 9, 27/5
under that assumption we have
s1 = 15
r = 3/5
sn = sn-1 × r = s1 × r^(n-1) = 15 × (3/5)^(n-1)
s10 = 15 × (3/5)⁹ = 15 × 19683/1953125 =
= 3 × 19683/390625 = 59049/390625 =
= 0.15116544 ≈ 0.151
9514 1404 393
Answer:
A) 504
B) 8
Step-by-step explanation:
The statement of proportionality can be written as the equation ...
m = kr²
Then we can find k from ...
k = m/r² = 14/2² = 7/2
That is, ...
m = (7/2)r²
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Using this relation, we can find m for r=12:
m = (7/2)·12² = 7·72
m = 504 . . . for r = 12
__
And, we can use the same equation to solve for r when m=224.
224 = 7/2·r²
r² = 64
r = √64
r = 8 . . . for m = 224
