(1)按声压级由小到大排列:L1=65dB L2=70 dB L3=75dB
(2)L2-L1 =70-65=5dB
查表 △L1=1.2dB
L c1=L1+ △L1= 70+1.2=71.2dB
(3) L3- L c1 =75-71.2=3.8dB
查表的 △L2=1.5dB
Lc2= L c1+ △L2=71.2+1.5=72.7dB
(1)按声压级由小到大排列:L1=65dB L2=70 dB L3=75dB
(2)L2-L1 =70-65=5dB
查表 △L1=1.2dB
L c1=L1+ △L1= 70+1.2=71.2dB
(3) L3- L c1 =75-71.2=3.8dB
查表的 △L2=1.5dB
Lc2= L c1+ △L2=71.2+1.5=72.7dB