If $^{6} P_{r} = 360$ and $^{6} C_{r} = 15$ ,then find $r ?$

5

No worries! We‘ve got your back. Try BYJU‘S free classes today!

6

No worries! We‘ve got your back. Try BYJU‘S free classes today!

4

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

3

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is C $4$
$\frac{6!}{(6 - r)!} = 360$
$\frac{6!}{(6 - r) r!} = 15$
$r! = \frac{360}{15} = 24$
$r = 4$

Suggest Corrections

Similar questions

r

(i)^{5} P_{r} = 2^{6} P_{r - 1} (i i)^{5} P_{r} =^{6} P_{r - 1}

r

^{5} P_{r} =^{6} P_{r - 1}

^{n} P_{r} = 360

^{n} C_{r} = 15

\frac{1}{^{5} C_{r}} + \frac{1}{^{6} C_{r}} = \frac{1}{^{4} C_{r}},

r

Find r if (i) (ii) .

Join BYJU'S Learning Program