" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
Rata rata x=∑xi.f/n
6=(4.20)+(5.40)+(6.70)+(8.a)+(10.10)/ (20+40+70+a+10)
=(80)+(200)+(420)+(8a)+(100)/(140+a)
=(800+8a)/(140+a)
6(140+a)=(800+8a)
840+6a=800+8a
6a-8a=800-840
-2a=-40
a=-40/-2
a=20
---
Pilihan B.
Demikian Semoga Membantu dan Bermanfaat!