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3 years ago

A jewelry box contains 13 gold earrings, 10 silver earrings and 12 titanium

Mathematics

1 answer:

gulaghasi [49]3 years ago

8 0

Answer:

The probability is 406/625

Step-by-step explanation:

If they are of different materials, we have the following combinations of selection;

(gold and silver) or ( silver and titanium) or (gold and titanium )

The number of earrings present is 13 + 10 + 12 = 25

Probability of selecting a gold earring is 13/25

Probability of a silver is 10/25

Probability of a titanium is 12/25

Substituting these into the probabilities, we have;

(13/25 * 10/25) + (10/25 * 12/25) + (13/25 * 12/25)

= 130/625 + 120/625 + 156/625 = 406/625

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Soloha48 [4]

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$\underbrace{\begin{bmatrix}1&6&6^2\\1&3&3^2\\\vdots&\vdots&\vdots\\1&9&9^2\end{bmatrix}}_{\mathbf A}\underbrace{\begin{bmatrix}a_0\\a_1\\a_2\end{bmatrix}}_{\mathbf x}=\underbrace{\begin{bmatrix}100\\110\\\vdots\\70\end{bmatrix}}_{\mathbf b}$

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4 years ago

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Step-by-step explanation:

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3 years ago

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3 years ago

Read 2 more answers

A cylinder has a radius of 6 centimeters and a height of 18 centimeters. A smaller cylinder has linear dimensions that are one-t

vlabodo [156]

Answer:

the larger cyclinder has a surface area which is 9 times the surface area of the smaller cyclinder.

Step-by-step explanation:

Surface area of larger cyclinder

Radius = 6cm

Height = 18cm

A = 2πrh + 2πr^2

= 2*3.14*6*18 + 2*3.14*6^2

= 678.24 + 226.08

= 904.32 cm

Smaller cyclinder (1/3 of the larger cyclinder)

Radius = 2cm

Height = 6cm

A = 2πrh + 2πr^2

= 2*3.14*2*6 + 2*3.14*2^2

= 75.36 + 25.12

= 100.48 cm

Comparing the surface area of the larger cyclinder and the smaller cyclinder

= 904.32 cm / 100.48 cm

= 9

This means, the larger cyclinder has a surface area which is 9 times the surface area of the smaller cyclinder.

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3 years ago

Write 6 over 10 in terminating decimal

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4 years ago