How do you simplify $(13r^7)/(39r^4)$ ?

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Answer 1 · 2017-04-28T12:40:02

$(r^3)/3$

You can write down tour equation again:

$(13*r^4*r^3)/(3*13*r^4)$

Now $13r^4$ s cancel each other

You get

$r^3/13$

This is your answer $r^3/13$

Answer 2 · 2017-04-28T12:42:42

$(13r^3)/39$

$color(blue)("First principle method")$

Note that 13 is a prime number so you can not simplify any further the value of $13/39$

Write as: $" "13/39xx(r^4xxr^3)/r^4$

$" "13/39xxr^4/r^4xxr^3$

But $r^4/r^4=1$ giving:

$" "13/39xx1xxr^3$

$" "(13r^3)/39$
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$color(blue)("Shortcut method")$

$(13r^7)/(39r^4)" "=" "(13r^(7-4))/39" "=(13r^3)/39$

How do you simplify (13r^7)/(39r^4)(13r^7)/(39r^4)?