	Hướng dẫn giải
a	Giá trị trung bình của s và t: $Title: top enclose straight s equals fraction numerator straight s subscript 1 plus straight s subscript 2 plus straight s subscript 3 plus straight s subscript 4 plus straight s subscript 5 over denominator 5 end fraction equals fraction numerator 0 comma 546 plus 0 comma 554 plus 0 comma 549 plus 0 comma 560 plus 0 comma 551 over denominator 5 end fraction equals 0 comma 552 space straight m space top enclose straight t equals fraction numerator straight t subscript 1 plus straight t subscript 2 plus straight t subscript 3 plus straight t subscript 4 plus straight t subscript 5 over denominator 5 end fraction equals fraction numerator 2 comma 47 plus 2 comma 51 plus 2 comma 42 plus 2 comma 52 plus 2 comma 48 over denominator 5 end fraction equals 2 comma 48 space straight s space$
	Sai số tuyệt đối trung bình của s v $Title: top enclose increment straight s end enclose equals fraction numerator open vertical bar top enclose straight s minus straight s subscript 1 close vertical bar plus open vertical bar top enclose straight s minus straight s subscript 2 close vertical bar plus open vertical bar top enclose straight s minus straight s subscript 3 close vertical bar plus open vertical bar top enclose straight s minus straight s subscript 4 close vertical bar plus open vertical bar top enclose straight s minus straight s subscript 5 close vertical bar over denominator 5 end fraction space space space space equals fraction numerator open vertical bar 0 comma 552 minus 0 comma 546 close vertical bar plus open vertical bar 0 comma 552 minus 0 comma 554 close vertical bar plus open vertical bar 0 comma 552 minus 0 comma 549 close vertical bar plus open vertical bar 0 comma 552 minus 0 comma 560 close vertical bar plus open vertical bar 0 comma 552 minus 0 comma 551 close vertical bar over denominator 5 end fraction equals 0 comma 004 space straight m. top enclose increment straight t end enclose equals fraction numerator open vertical bar top enclose straight t minus straight t subscript 1 close vertical bar plus open vertical bar top enclose straight t minus straight t subscript 2 close vertical bar plus open vertical bar top enclose straight t minus straight t subscript 3 close vertical bar plus open vertical bar top enclose straight t minus straight t subscript 4 close vertical bar plus open vertical bar top enclose straight t minus straight t subscript 5 close vertical bar over denominator 5 end fraction space space space space equals fraction numerator open vertical bar 2 comma 48 minus 2 comma 47 close vertical bar plus open vertical bar 2 comma 48 minus 2 comma 51 close vertical bar plus open vertical bar 2 comma 48 minus 2 comma 42 close vertical bar plus open vertical bar 2 comma 48 minus 2 comma 52 close vertical bar plus open vertical bar 2 comma 48 minus 2 comma 52 close vertical bar over denominator 5 end fraction equals 0 comma 04 space straight s.$
	Sai số tuyệt đối của s và t
b	Giá trị trung bình của v: $Title: straight v with bar on top equals fraction numerator straight s with bar on top over denominator straight t with bar on top end fraction equals fraction numerator 0 comma 552 over denominator 2 comma 48 end fraction equals 0 comma 223 space straight m divided by straight s$ Sai số tuyệt đối của v: $Title: fraction numerator increment straight v over denominator straight v with bar on top end fraction equals fraction numerator increment straight s over denominator straight s with bar on top end fraction plus fraction numerator increment straight t over denominator straight t with bar on top end fraction equals fraction numerator 0 comma 005 over denominator 0 comma 552 end fraction plus fraction numerator 0 comma 05 over denominator 2 comma 48 end fraction rightwards double arrow increment straight v equals open parentheses fraction numerator 0 comma 005 over denominator 0 comma 552 end fraction plus fraction numerator 0 comma 05 over denominator 2 comma 48 end fraction close parentheses cross times straight v with bar on top equals open parentheses fraction numerator 0 comma 005 over denominator 0 comma 552 end fraction plus fraction numerator 0 comma 05 over denominator 2 comma 48 end fraction close parentheses cross times 0 comma 223 equals 0 comma 007 space straight m divided by straight s.$
b	Kết quả đo gia tốc rơi tự do được viết dưới dạng: v = (0,223 ± 0,007) m/s.

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