Question

Media aritmetica a numerelor a1 , a2 ,a3 ,...,a10 este 41,iar a10 =50.Calculati media aritmetica a numerelor a1 ,a2,a3,....,a9

Answer 1

Ma=a1+a2+a3+...+a10/10=41
a1+a2+a3+...+a10=410
a10=50
a1+a2+a3+...+a9=410-50=360
Ma=a1+a2+a3+...+a9/9=360/9=40

Answer 2

                               
$m_{a1} = \frac{a_1+a_2+a_3+a_4+a_5+a_6+a_7+a_8+a_9+a_{10}}{10}=41 \\ \\ a_{10}=50 \\ \\ m_{a1} = \frac{a_1+a_2+a_3+a_4+a_5+a_6+a_7+a_8+a_9+50}{10}=41 \\ \\ => S=a_1+a_2+a_3+a_4+a_5+a_6+a_7+a_8+a_9+50 = 41 * 10 \\ S=a_1+a_2+a_3+a_4+a_5+a_6+a_7+a_8+a_9+50 = 410 \\ a_1+a_2+a_3+a_4+a_5+a_6+a_7+a_8+a_9 = 410-50 = 360 \\ \\ => m_{a2} =\frac{a_1+a_2+a_3+a_4+a_5+a_6+a_7+a_8+a_9}{9}= \frac{360}{9}=40$