Khan/khan-exercises

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 Writing proportions
randRange( 2, 10 ) randRangeExclude( 2, 15, [ N1 ] ) localeToFixed( N1 * randRange( 80, 199 ) / 100, 2) "\\dfrac{" + N1 + "}{\\$" + C + "} = \\dfrac{" + N2 + "}{x}" N1 plural_form(deskItem(0), N1) cost \$C.

Which equation would help determine the cost of N2 plural_form(deskItem(0), N2)?

SOLUTION

• \dfrac{N2}{\$C} = \dfrac{x}{N1} • \dfrac{N2}{N1} = \dfrac{\$C}{x}
• \dfrac{N1}{N2} = \dfrac{x}{\$C} • \dfrac{x}{N2} = \dfrac{N1}{\$C}
• \dfrac{N2}{x} = \dfrac{\$C}{N1} We can write the fact that N1 plural_form(deskItem(0), N1) cost \$C as a proportion:

\qquad \dfrac{N1}{\$C} Let x represent the unknown cost of N2 plural_form(deskItem(0), N2). Since N2 plural_form(deskItem(0), N2) cost x, we have the following proportion: \qquad \dfrac{N2}{x} The cost changes along with the number of plural_form(deskItem(0)) purchased, and so the two proportions are equivalent. \qquad SOLUTION "\\dfrac{" + N2 + "}{x} = \\dfrac{" + N1 + "}{\\$" + C + "}"

Let x represent the unknown cost of N2 plural_form(deskItem(0), N2). Since N2 plural_form(deskItem(0), N2) cost x, we have the following proportion:

We can write the fact that N1 plural_form(deskItem(0), N1) cost \$C as a proportion: \qquad \dfrac{N1}{\$C}

The cost changes along with the number of plural_form(deskItem(0)) purchased, and so the two proportions are equivalent.

"\\dfrac{" + N1 + "}{" + N2 + "} = \\dfrac{\\$" + C + "}{x}" We know the cost of N1 plural_form(deskItem(0), N1). We want to know the cost of N2 plural_form(deskItem(0), N2). We can write the numbers of plural_form(deskItem(0)) as a proportion: \qquad \dfrac{N1}{N2} We know N1 plural_form(deskItem(0), N1) costs \$C. We can let x represent the unknown cost of N2 plural_form(deskItem(0), N2). The proportion of these costs can be expressed as:

\qquad \dfrac{\$C}{x} The cost changes along with the number of plural_form(deskItem(0)) purchased, and so the two proportions are equivalent. \qquad SOLUTION "\\dfrac{x}{" + N2 + "} = \\dfrac{\\$" + C + "}{" + N1 + "}"

If we let x represent the cost of N2 plural_form(deskItem(0), N2), we have the following proportion:

We have to pay \$C for N1 plural_form(deskItem(0), N1), and that can be written as a proportion: \qquad \dfrac{\$C}{N1}