Select the number combination of letters that when placed sequentially in the blanks of the given series will complete the series.\
a b c _ e _ g _ b _ d _ f _ a _ c _ e _ g _ b _ d _ f _
The complete series will be: a b c d e f g / a b c d e f g / a b c d e f g / a b c d e f g
(? + 6.063.03 ) ÷ 10.08 + 21.89 × 6.97 = 1979.97 ÷ 10.96
8.992 + (5.01 × 4.98) + ? = 224.03
25.19% of (?2 ÷ 38.87 × 4679.94) = 6299.82 ÷ 419.78 × 50.15
12.99% of 399.99 ÷ 13.17 = ? ÷ 18.15
(51.99² - 19.05² )÷ ? = 14.11² - 140.33
?% of (128.31 ÷ 15.97 × 75.011) = 419.98
25.31% of 5199.90 + (19.9 × 17.11) + 46.021 =? + 168.98
(10.98% of 499.99) - 4.998 = √?
6940 ÷ 28 ÷ 7 =?