<span>3т8ц *40=38ц*40=1520ц=152т</span>
А)9м-34дм+2м9дм=6м5дм
36дм=3м6дм
3м6дм+2м9дм=6м5дм
б)1м-4дм8см-1дм7см=35см
560см=0,56м ; 81мм=8,1см; 37мм= 3,7см; 20см=2дм; 70см=7дм, 3дм=30см; 8дм=80см; 60дм=0,6м; 90дм=0,9м; 4м=40дм; 5м=50дм.
1) 24/65·39/40 = 24·39/65·40 = 3·39/65·5=3.3/5·5 = 9/25
2) 3/7·(5+3/5)= 3/7 · 28/5 = 3/1 ·4/5 = 12/5 = 2 + 2/5 т,е, 2 целых 2/5
3) 3/8 · (2+2/3) = 3/8 ·8/3 = 1