а) А1. Pop25
1 2 O
225
x
19 26 (4)
3 24 ОФа
a62b0
Answers
Answered by
1
Answer:
A1+a
5
+a
10
+a
15
+a
20
+a
24
=225
⇒6a+69d=225
⇒2a+23d=75
a
1
+a
2
+a
3
+...+a
23
+a
24
=S
24
S
24
=12(2a+23d)
=900
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