Find the missing number (1+_ ÷7+4)÷8=4/7

Mathematics

1 answer:

GaryK [48]3 years ago

3 0

The answer to (1+_÷7+4)÷8= 4/7 is -3 I believe

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What is X squared +3x-70

Aleksandr-060686 [28]

Answer:

x = 7, x = -10

Step-by-step explanation:

$x^2+3x-70 = 0$

Use the quadratic formula.

$x = \frac{-3 + \sqrt{3^2-4(1)(-70)} }{2(1)} \\x = \frac{-3 - \sqrt{3^2-4(1)(-70)} }{2(1)} \\$

Solve.

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They are dependent events. Event A is choosing one musician while Event B is choosing another musician. THey are ALL musicians, no matter what instrument they play, we just know that there are 7 musicians in total. Therefore, the events are dependent because after choosing one musician, you would have 6 musicians left, instead of 7.

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The wildlife department has been feeding a special food to rainbow trout fingerlings in a pond. based on a large number of obser

Liono4ka [1.6K]

The normal distribution curve for the problem is shown below

We need to standardise the value X=405.5 by using the formula

$z-score= \frac{X-Mean}{Standard Deviation}$
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We now need to find the probability of z=0.32 by reading the z-table

Note that z-table would give the reading to the left of z-score, so if your aim is to work out the area to the right of a z-score, then you'd need to do:

$P(Z\ \textgreater \ z)=1 - P(Z\ \textless \ z)$

from the z-table, the reading $P(Z\ \textless \ 0.32)$ gives 0.6255

hence,
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