$=[1\times3+1\times0.5+0.2\times3+0.2\times0.5](4+0.1)$
$=(3+0.5+0.6+0.1)(4+0.1)$
$=(4.2)(4+0.1)=(4+0.2)(4+0.1)$
$=4\times4+4\times0.1+0.2\times4+0.2\times0.1$
$=16+0.4+0.8+0.02=17.22$
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