Question

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求加权平均数
1、数据21、32、43、54以3/10,4/10,2/10,1/10为权数

2、数据21、32、43、54以以0.2,0.3,0.1,0.4为权数

Answer 1

21*3/10+32*4/10+43*2/10+54*1/10
=6.3+12.8+8.6+5.4
=33.1

21*0.2+32*0.3+43*0.1+54*0.4
=4.2+9.6+4.3+21.6
=39.7

Answer 2

（1）21×3/10+32×4/10+43×2/10+54×1/10
=6.3+12.8+8.6+5.4
=33.1
（2）21×0.2+32×0.3+43×0.1+54×0.4
=4.2+9.6+4.3+21.6
=39.7.

Answer 3

答案解法如下：
(1)21x3/10+32x4/10+43x2/10+54x1/10=33.1

(2)21x0.2+32x0.3+43x0.1+54x0.4=39.7

Answer 4

33.1
39.7