Answer:
8 days
Step-by-step explanation:
On day 8, Isabella will save 256 nickels, bringing her total to 510.
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The number of nickels saved on day n is 2^n. The total is 2^(n+1)-2.
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The above can be written down from your knowledge of binary sequences. If you want a more formal development, read on.
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The number of nickels saved on day n is a geometric sequence with first term 2 and common ratio 2. The n-th term of the sequence is ...
an = a1·r^(n-1) = 2·2^(n-1) = 2^n
The sum of n terms of the sequence is ...
S = a1(r^n -1)/(r -1) = 2(2^n -1)/(2-1)
S = 2^(n+1) -2
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We want S > 500, so ...
500 < 2^(n+1) -2
502 < 2^(n+1)
251 < 2^n
log(251) < n·log(2)
n > log(251)/log(2)
n > 7.97 . . . . . . . . 8 days or more to save more than 500 nickels
Well 2.4/ 16.4 is 6.9, but idk if that is what u were asking for
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Define length and width
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Let x be the width
width = x
Length = 2x + 4
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Formula
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Perimeter = 2(length + width)
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Find Length and width
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62 = 2(2x + 4 + x)
62 = 2(3x + 4) <em> ← combine like terms </em>
62 = 6x + 8 <em>← remove bracket </em>
62 - 8 = 6x <em>← minus 8 on both sides </em>
6x = 54 <em> ← swap sides </em>
x = 54 ÷ 6 <em>← divide by 6 on both sides</em>
<em>x = 9 m</em>
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Find Length and Width
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Width = x = 9 m
Length = 2x + 4 = 2(9) + 4 = 22 m
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Answer: Length = 22m
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Answer:
HERE IS YOUR ANSWER
Step-by-step explanation:
Use the mirror equation:
1/di + 1/do = 1/f
where di = -10 cm and f = +15 cm. (Note that di is negative if the image is virtual.)
Substitute and solve for do.
1/do + 1/(-10 cm) = 1/(15 cm)
1/do = 1/(15 cm) - 1/(-10 cm) = 5/(30 cm)
do = 6 cm
Hope it helps you
Regards,
Rachana
Answer:
s=x/3+10/3
Step-by-step explanation: