Andrew is showing his work in simplifying −4.5 + 4.2 + 5.6 − 7.3. Identify any errors in his work or in his reasoning.

Mathematics

1 answer:

julia-pushkina [17]3 years ago

6 0

Answer:

D. Step 5

Step-by-step explanation:

Andrew made a mistake at last step.

<u>It should be:</u>

-11.8 + 9.8 = 9.8 - 11.8 = -2 but not -21.6

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Mademuasel [1]

Answer:

Step-by-step explanation:

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4 years ago

A group of five people are all working on the same mathematics problem. On the night before it is due, they call each other to d

UkoKoshka [18]

Answer:

Minimum number of calls = 10

Step-by-step explanation:

Lets name the five people as A,B,C,D and E.

<u>On the night before ,each person talks to every other person atleast once that means A would talk to B,C,D and E atleast once.</u>

Lets start with A. He would talk to other 4 people which means there would be 4 phone calls made.

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For D , he talks to E alone.

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3 years ago

The strength of a cable is proportional to the square of its diameter. If a 2-cm cable will support 800kg, how much will a 3-cm

xz_007 [3.2K]

Strength [is proportional to] d^2
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strength2 = 800 kg * (3 cm)^2/(2 cm)^2
strength2 = 800 kg * 3^2/2^2
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4 years ago

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Answer:

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Step-by-step explanation:

Sometimes, a simple drawing is a great way to start! In the attached drawing, the red line represents the ladder, the brown represents the ground, and the black represents the building!

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$sin\theta=\frac{opposite}{hypotenuse}$