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2 years ago

A jewelry store has 311.75 ounces of 14-carat gold in stock.

Mathematics

1 answer:

WARRIOR [948]2 years ago

4 0

Answer:

$\boxed{\text{(a) 86 necklaces; (b) \$2220}}$

Step-by-step explanation:

(a) Number of necklaces

3⁵/₈ = 3.625

$\text{No. of necklaces} = 311.75\text{ oz} \times \dfrac{\text{1 necklace}}{3.625\text{ oz}} = \textbf{ 86 necklaces}\\\\\text{You can make } \boxed{\textbf{86 necklaces}} \text{ from 311.75 oz of 14K gold}$

(b) Value of gold in each necklace

There are 3.625 oz of 14K gold in each necklace. Pure gold is 24K.

$\text{Mass of pure gold} = \text{3.625 oz} \times \dfrac{\text{14K}}{\text{24K}} = \text{2.1146 oz}$

Pure 24K gold is worth $1050/oz.

$\text{Value of pure gold} = \text{2.1146 oz} \times \dfrac{\text{\$1050}}{\text{1 oz}} = \textbf{\$2220}\\\\\text{The value of the gold in each necklace is } \boxed{\textbf{\$2220}}$

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Answer:

Step-by-step explanation:

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The parallel vector to the line i + zj+k = ai + bj + ck

Hence, the equation for the line is :

$x = x_o + at \\ \\ x = y_o + bt \\ \\ x = z_o + ct$

x = 4 + t

y = -5 + 2t

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Thus, x, y, z = ( 4+t, -5+2t, 2+t )

The symmetric equation can now be as follows:

$\begin {vmatrix} x = 4+ t \\ \\ \dfrac{x-4}{1} = t \begin {vmatirx} \end {vmatrix}$ $\begin {vmatrix} y = - 5+2t \\ \\ \dfrac{y+5}{2} =t \end {vmatrix}$ $\begin {vmatrix} z =2+t \\ \\ \dfrac{z-2}{1} =t \end {vmatrix}$

∴

$\dfrac{x-4}{1}= \dfrac{y+5}{2}=\dfrac{z-2}{1}$

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2 years ago

18. cos t(sec t - cos t)

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What is the radius of the circle who’s equation is x^2 + y^2 = 9

Svetllana [295]

Answer:

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Step-by-step explanation:

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