Sure, let's solve each of these equations step by step.
### Equation (a)
[tex]\[
\frac{2}{5} = \frac{x}{15}
\][/tex]
To solve for [tex]\( x \)[/tex], use cross-multiplication:
[tex]\[
2 \cdot 15 = 5 \cdot x \\
30 = 5x \\
x = \frac{30}{5} \\
x = 6
\][/tex]
### Equation (b)
[tex]\[
\frac{4}{3} = \frac{x}{7}
\][/tex]
Again, use cross-multiplication:
[tex]\[
4 \cdot 7 = 3 \cdot x \\
28 = 3x \\
x = \frac{28}{3} \\
x \approx 9.333
\][/tex]
### Equation (c)
[tex]\[
\frac{7}{5} = \frac{28}{x}
\][/tex]
Cross-multiply to solve for [tex]\( x \)[/tex]:
[tex]\[
7 \cdot x = 5 \cdot 28 \\
7x = 140 \\
x = \frac{140}{7} \\
x = 20
\][/tex]
### Equation (d)
[tex]\[
\frac{11}{4} = \frac{5}{x}
\][/tex]
Use cross-multiplication:
[tex]\[
11 \cdot x = 4 \cdot 5 \\
11x = 20 \\
x = \frac{20}{11} \\
x \approx 1.818
\][/tex]
### Summary of Solutions
So, the solutions to the equations are:
a. [tex]\( x = 6 \)[/tex]
b. [tex]\( x \approx 9.333 \)[/tex]
c. [tex]\( x = 20 \)[/tex]
d. [tex]\( x \approx 1.818 \)[/tex]
