These real numbers can be taken as 8 quantities,
a−5, a−4, a−3, a−3, a−3, 1, a8, a10 .
All are positive as a >0
∴ AM>GM (as all quantities are not distinct)$
∴ 81[a−5+a−4+a−3+a−3+a−3+1+a8+a10]
≥(a−5 ⋅ a−4 ⋅ a−3 ⋅ a−3 ⋅ a−3 ⋅ 1 ⋅ a8 ⋅ a10)1 / 8
⇒ 81[a−5+a−4+a−3+a−3+a−3+1+a8+a10] ≥ 11 / 8
⇒ (a−5+a−4+a−3+a−3+a−3+1+a8+a10) ≥ 8
∴ Minimum value of the sum is 8.