Question

{1\24.25 + 1\25.26 +...+ 1\29.30} .120+x:1\3 = -4

Answer 1

(1/24.25 + 1/25.26 + ... + 1/29.30) . 120 + x : 1/3 = -4

(1/24 - 1/25 + 1/25 - 1/26 + ... + 1/29 - 1/30) . 120 + x . 3 = -4

(1/24 - 1/30) . 120 + x . 3 = -4

(5/120 - 4/120) + x . 3 = -4

=> 1/120 . 120 + x . 3 = -4

=> 1 + x . 3 = -4

=> x . 3 = -4 - 1

=> x . 3 = -5

=> x = -5/3

Vậy x = -5/3

Answer 2

{1\24.25 + 1\25.26 +...+ 1\29.30} .120+x:1\3 = -4