Question

please tell me this question

Answer 1

I will tell you the answer........
$\binom{a + 3}{4} + \binom{a + 6}{5} = 7$
$(5a + 15 + 4a + 24) \div 20 = 7$
$9a + 39 = 140$
$9a = 101$
$a = 11.22$

Answer 2

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