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1 year ago

Estimate the product 8.1 x 4.2

Mathematics

1 answer:

Korvikt [17]1 year ago

6 0

Round 8.1 down to 8
Round 4.2 down to 4

8(4)= 32

The estimated product is 32.
Hope this helps!

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Previous Question Question 14 of 20 Next Question A company randomly surveys 15 VIP customers and records their customer satisfa

Ann [662]

Answer:

71.4699, 81.7301.

Step-by-step explanation:

So, the following are the scores: 74

$Let,\;the\;total\;sum\;of\;the\;scores\;be:\sum x =1149$

$Then,\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\sum x^2=89795$

The length of the score : 15

Then, let the size of the scores be n : 15.

Then, we have to find the mean.

$\bar{x}=\frac{\sum x}{n}$

$=\frac{1149}{15}=76.6$

$Then,\;we\;have\;to\;find\;standard\;deviation:S=\sqrt{\frac{\sum x^2-n.(\bar{x})^2}{n-1} }$

$=\sqrt{\frac{89795-15\times(76.6)^2}{15-1} }=11.2808$

$The\;degree\;of\;freedom:n-1=14$

$So,\;the\;significant\;level:\alpha=1-0.90=0.10$

$and\;the\;critical\;value:t_{\frac{\alpha}{2} }=1.7613$

$Finally:\\=\bar{x}\;\pm\;t_{\frac{\alpha}{2} }\;\frac{S}{\sqrt{n} }\\=(71.4699, 81.7301)$

6 0

2 years ago

Betty saves 3 times as much as Ann. Charles save 390 less than Ann.. If Betty saves save 1330 more than Charles. how much does C

Igoryamba

Answer:

Step-by-step explanation:

We let x be Ann's savings.

Betty saves 3 times as much as Ann.

This implies that Betty's savings in terms of x

$= 3x$

Charles save 390 less than Ann.

This implies Charles savings

$= x - 390$

Betty saves 1330 more than Charles.

This implies that when we deduct Charles savings from Betty's we have to get 1330.

Mathematical equation for the problem:

$3x - (x - 390) = 1330$

Expand :

$\implies 3x - x + 390= 1330$

$\implies 2x + 390= 1330$

Subtract 390 from both sides.

$\implies 2x + 390 - 390= 1330 - 390$

$\implies 2x=940$

Divide through by 2

$\implies \frac{2x}{2} = \frac{940}{2}$

$\implies x=470$

Hence Charles saving is

$x - 390 = 470 - 390 = 80$

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2 years ago

Tim installs 50 square feet of his floor in 45 minutes. At this rate, how long does it take him to install 495 square feet? (Ple

Alenkinab [10]

Answer:

445.5min=595²ft

Step-by-step explanation:

y=0.9x

y=0.9*495

y=445.5

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1 year ago

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How would the fraction 1/3+square root of 2 be rewritten if its denominator is rationalized using difference of squares? A. 3-sq

Vera_Pavlovna [14]

given 1 /( 3 + √2 )

then rationalise the denominator by multiplying the numerator/ denominator by the conjugate of the denominator

the conjugate of 3 + √2 is 3 - √2

1 / (3 + √2 ) × (3 - √2 ) / (3 - √2 )

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What is the lateral area of a right rectangular prism that has rectangular bases measuring 3" by 5" and a height of 6"?

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The answer is the option A

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$P=2*(3+5)=16\ in$

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1 year ago

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