If the two terms of a gemotric sequence are a1=216, and a2=72, which is the third term? a3?

1 answer:

4 0

$GEOMETRIC \: \: PROGRESSIONS \\ \\ \\\\Let \: the \: G.P. \: be \: \: A \: , \: Ar \: , \: A {r}^{2} \: ... \\ \\ Where \:first \: term \: is \: \: A \: \: \\ and \: common \: ratio \: is \: \: R \\ \\ Let \: An \: denotes \: the \: \: nth \: term \: of \: \\ the \: given \: Geometric \: Progression \: \\ \\ It \: is \: given \: - \\ \\ A1 \: = \: 72 \\ \\ A2 \: = \: 216 \\ \\ Common \: ratio \: = \: \frac{A2}{A1} = \frac{216}{72} \\ \\ R = 3 \\ \\ A \: = \: 72 \\ \\ A3 \: = \: A {r}^{2} = 72 \times 3 \times 3 \\ \\ \\ Hence \: , \: A3 \: = \: 648 \: \: \: \: \: \: \: Ans.$

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Which mixed number is equal to 27/6?

zmey [24]

Answer:

4 $\frac{3}{6}$

Step-by-step explanation:

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2 years ago

Work out the area of this semi circle

kirill [66]

Answer:

39.27

Step-by-step explanation:

The area of a semi-circle is pi times the radius squared divided by 2. So basically standard area of a circle formula (pi times the radius squared) but then you add in the extra step of dividing it by 2.

The formula looks like this:

π × r² ÷ 2

The radius is half the diameter of the circle. So basically think of it as a line to the middle of the circle. Our diameter is 10, (the diameter is the entire length of the circle. It gives us this already. If you need diameter and only have the radius add the radius together twice or multiply it by 2 to get the diameter. Fun fact..?)

and it tells us to substitute pi for 3.142.

So, plugging our numbers in we get:

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Cut out the 3rd decimal place (5) as it tells us to only include the first 2 decimal places, and we finally end up with 39.27.

<u>Hope this helps and have a nice day!</u>

5 0

2 years ago

Last year 762 students voted in the student council election at San Bruno Middle School this year 721 students voted to the near

Soloha48 [4]

Answer:

Percent change = 5.4%

Step-by-step explanation:

Given:

Number of students voted last year = 762

Number of students voted this year = 721

Change in the number of students who voted from last year to this year is given by the difference of their number. This gives,

Change in the number of students that voted = 762 - 721 = 41

Now, percentage change in the number of students that voted is given as:

$\textrm{Pecent change}=\frac{\textrm{Change in number}}{\textrm{Number last year}}\times 100\\\\\textrm{Pecent change}=\frac{41}{762}\times 100\\\\\textrm{Pecent change}=\frac{4100}{762}=5.38\%\approx 5.4\%$