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3 years ago

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Find the sum of the first 90 terms of the sequence –4, –1, 2, 5, 8, ...

2 answers:

Aleks04 [339]3 years ago

8 0

Hello :
-1-(-4) =2-(-1)=5-2=8-5=3 ( arhtmitic sequence r= 3)
Un = U1+(n-1)r
U90 = -4+(90-1)(3)= 263
sum = n/2 (U1 +U90)
sum = 90/2(-4+263) = 11655

Juli2301 [7.4K]3 years ago

6 0

Answer:

11655 is correct

Step-by-step explanation:

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4 years ago

If the coefficient of determination for a data set is 0.75 and the SSE for the data set is 13, what is the SST for the data set?

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4 years ago

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Find three consicutive numbers that have the sum 96

In-s [12.5K]

Answer:

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Step-by-step explanation:

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2 years ago

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Answer:

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Step-by-step explanation:

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