Question

The diagram shows the length and width of a cell phone, and the length of a larger version of the same brand of cell phone. hin 02112 The lengths and widths of the two cell phones are proportional. What is the widih, in inches, of the larger version of the cell phone?A. 1.15, B.2.26, C.2.99, D.3.41

Answer 1

∵ The 2 cell phones are proportional

∴ Their dimensions are proportional

$\frac{l_1}{l_2}=\frac{w_1}{w_2}$

∵ l1 = 5.4 in and l2 = 6.21

∵ w1 = 2.6 in and w2 = ?

Substitute them in the ratio above

$\frac{5.4}{6.21}=\frac{2.6}{w_2}$

By using cross multiplication

$\begin{gathered} 5.4\times w_2=6.21\times2.6 \\ 5.4w_2=16.146 \end{gathered}$

Divide both sides by 5.4

$\begin{gathered} \frac{5.4w_2}{5.4}=\frac{16.146}{5.4} \\ w_2=2.99 \end{gathered}$

The width of the larger cell phone is 2.99 in

The answer is C