Please help! 10 ∑ 2i-9 i=3

1 answer:

6 0

$\sum\limits_{i=3}^{10}(2i-9)=2(3)-9+2(4)-9+2(5)-9+2(6)-9+2(7)-9\\\\+2(8)-9+2(9)-9+2(10)-9\\\\=6-9+8-9+10-9+12-9+14-9+16-9+18-9+20-9\\\\=90-72=18$

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KonstantinChe [14]

Answer: Expression for the amount raised by Rachel = x
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zhenek [66]

Answer:

Total number of arrangements = 1,663,200

Step-by-step explanation:

Given:

11 - letter

FIRECRACKER

F = 1

I = 1

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E = 2

C = 2

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K = 1

Find:

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Computation:

Note: Repeated letter will be avoid.

$Number\ of\ arrangements = \frac{!11}{!3 \times !2 \times !2}\\\\Number\ of\ arrangements = \frac{!11}{!3 \times !2 \times !2} \\\\Number\ of\ arrangements = \frac{11 \times 10 \times 9 \times 8 \times 7 \times 6 \times 5 \times 4 \times 3}{3 \times 2 \times 2 } \\\\Number\ of\ arrangements = 1,663,200$