Question

find x if 25x/5*15/4=21​

Answer 1

Answer:

25x/5*15/4=21

5x*15/4=21

5x*15=84

x=84/75......

25/5*84/75*15/4=21

21=21

Answer 2

Answer:

$\frac{25x}{5}\cdot \frac{15}{4}=21\quad :\quad x=\frac{28}{25}\quad \left(\mathrm{Decimal}:\quad x=1.12\right)$

Step-by-step explanation:

$\frac{25x}{5}\cdot \frac{15}{4}=21$

$\gray{\mathrm{Divide\:the\:numbers:}\:\frac{25}{5}=5}$

$5\cdot \frac{15}{4}x=21$

$\gray{\mathrm{Multiply\:fractions}:\quad \:a\cdot \frac{b}{c}=\frac{a\:\cdot \:b}{c}}$

$\frac{15\cdot \:5}{4}x=21$

$\gray{\mathrm{Multiply\:the\:numbers:}\:15\cdot \:5=75}$

$\frac{75}{4}x=21$

$\gray{\mathrm{Multiply\:both\:sides\:by\:}4}$

$4\cdot \frac{75}{4}x=21\cdot \:4$

$\gray{\mathrm{Simplify}}$

$75x=84$

$\gray{\mathrm{Divide\:both\:sides\:by\:}75}$

$\frac{75x}{75}=\frac{84}{75}$

$\gray{\mathrm{Simplify}}$

$x=\frac{28}{25}$