4 years ago

Explain using the basic fact can help you find 10×20×30×40 mentally

1 answer:

8 0

Multiply 20 by 10 first
Then 200 by 30 which is 6000
Then 6000 by 40 which is 240000

Basically just multiply the numbers that's aren't 0
Like 2 in 200 times 3 in 30
Which is 6 then add the 0s so 6+000=6000

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What is the value of k in the equation below? 5k - 2k = 12? 1 1/5, 1 5/7, 3, 4

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<h3> $E=z_{\frac{\alpha}{2} }*\frac{\sigma}{\sqrt{n} }\\\\\sqrt{n}= z_{\frac{\alpha}{2} }*\frac{\sigma}{E }\\ \\n=( z_{\frac{\alpha}{2} }*\frac{\sigma}{E })^2\\\\Substituting:\\\\n=(2.58*\frac{29}{3} )^2=622.0036\\\\\\n=623(to\ the \ next\ whole\ number)$ </h3>

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4 years ago

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