Question

Find an irrational number between 5/7 and 7/9. How many more there may be?

Answer 1

1 irrational number between $\frac{5}{7} and \frac{7}{9} is:$
⇒$\frac{ \sqrt{5} * \sqrt{7} }{ \sqrt{7}* \sqrt{9} }$
⇒$= \sqrt{\frac{5}{9} }$
Between 2 numbers , there could exist 
∞ rational numbers and ∞ irrational numbers.

Answer 2

Answer:

Divide 5/7 and 7/9

5/7=0.714258....... .

7/9=0.777777......... .

Irrational numbers are:

0.720720072000720000.......

0.7340734007340007340000.......

0.740740074000740000........

0.7567056700567000567000056..........