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3 years ago

What is the sum of the first five terms of a geometric series with a1 = 20 and r = 1/4?

1 answer:

4 0

Sum of the first n terms of a geometric sequence is Sn = a(1 - r^n)/(1 - r)
Sn = 20(1 - (1/4)^5)/(1 - 1/4) = 20(1 - 1/1024)/(3/4) = 20(1023/1024)/(3/4) = 26 41/64

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Andy is solving a quadratic equation using completing the square. If a step in the process results in 169/9 = (x – 6)2, could th

natta225 [31]

Yes the equation can be solved by factoring. Using the given equation take the square root of both sides. Both 169 and 9 are perfect squares so the left side becomes plus or minus 13/3 which is rational. Six plus 13/3 is also a rational number. If the solutions of a quadratic equation are rational then the equation is factorable. Please mark a good rating and brainlest

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3 years ago

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Given m|n, find the value of x.

yaroslaw [1]

X=12

Because 180-168= 12

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3 years ago

<img src="https://tex.z-dn.net/?f=%2826%20%5Cdiv%20100%29%20%20%5C%3A%20%20%5C%3A%20%20%5C%3A%20%20%5C%3A%20%20%5Ctimes%2010" id

taurus [48]

Answer:

$\boxed{\bf \: \cfrac{13}{5}}$

Or in Decimal:

$\boxed{\bf \: 2.6}$

Step-by-step explanation:

Given expression :-

$\sf \: ( 26 \div 100) \times 10$

Solution :-

$\sf = (26 \div 100 )\times 10$

This arithmetic expression may be rewritten as ;

$\sf = \cfrac{26}{100} \times 10$

Step 1 : Cancel the zero of 10 and one zero of 100 :-

$\sf = \cfrac{26}{10 \cancel0} \times 1 \cancel0$

Results to;

$\sf = \: \cfrac{26}{10} \times 1$

$\sf = \: \cfrac{26}{10}$

Step 2: Cancel 26 and 10 by 2 :-

$\sf = \cfrac{ \cancel{26}}{ \cancel{10}}$

Results to;

$\sf = \cfrac{ \cancel{26} {}^{13} }{ \cancel{10} {}^{5} }$

$\sf = \cfrac{13}{5}$

It can also be in Decimal.

That is;

$\sf = 2.6$

Hence, the answer of the expression would be 13/5 or 2.6 .

$\rule{225pt}{2pt}$

I hope this helps!

Let me know if you have any questions.

I am joyous to help!

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3 years ago

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why do whole numbers raised to an exponent get greater while fractions raised to an exponent get smaller?

ehidna [41]

Any number above 1 gets greater, below 1 smaller (when above 0), while 1 itself remains the same. Negative numbers are more unpredictable.

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3 years ago

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At 9 a.m. a car (A) began a journey from a point, traveling at 40 mph. At 10 a.m.

Kisachek [45]

At three hours as car a has already traveled a hour which making it three therefore making car b equal 2 hours or in a math equation 40×3=car b and 60×2=car a

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