1)(0,45×0,72)×1,3=0,324×1,3=0,4212
2)(1,7×1,1)×(4,5×6,9)=1,87×31,05=58,0635
3)(3,6×0,76)×0,25=2,736×0,25=0,684
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(1,5×1,2)×(0,65×0,45)×(0,23×0,9)×(6,8×0,19)×(5,5×0,5)=1,8×0,2925×0,207×1,292×2,75=(1,8×0,207)×(0,75×1,292)×0,2925=0,3726×0,969×0,2925=0,3610494×0,2925=0,1056069495
4)(0,25×4,2)×(18,6×5,7)=1,05×106,02=111,321
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(1,9×3,1)×(1,26×0,5)=5,89×0,63=3,7107