Question

Multiply and write your answer in lowest terms: 21/26 x 39/42

Answer 1

ok so what u got till nw ?

Answer 2

if you are good at arithmetic (memorized the multiplication table!) you can change this problem to
\[ \frac{21}{26}\cdot \frac{39}{42} = \frac{3\cdot 7\cdot 3 \cdot 13}{2\cdot 13\cdot 6\cdot 7}\]

Answer 3

notice that a 7 is in both the top and bottom, which means 7/7 which is 1
you can "cancel" the 7's from the top and bottom
ask cancel the 13's

you are left with
\[ \frac{3 \cdot 3}{2 \cdot 6} \]
notice that the 6 can be written as 2*3, so
\[ \frac{3 \cdot 3}{2 \cdot 2 \cdot 3} \]
we have a 3 up top and in the bottom, so cancel a pair of 3's to get
\[ \frac{3}{2 \cdot 2} \]

Answer 4

That was the best explanation! thank you! :)