1 час = 60 мин
7 мин= 7/60 часа
14 мин =14/60=7/15 часа
1 час = 3600 сек
48 сек= 48/3600=1/75 часа
Ответ:
умножаем 1/3 на 2 и получаем 2/6
Пошаговое объяснение:
1) 9-2/3+6 7/24-2 1/4
9-2/3=27/3-2/3=25/3= 8 1/3
6 7/24-2 1/4=4+(7/24-6/24)=4 1/24
8 1/3+4 1/24=12+(8/24+1/24)=12 3/8
2) 8 13/30+13 4/5-5 5/6+7/10
8 13/30+7/10=8+(13/30+21/30)=9 2/15
9 2/15+13 4/5=22+(2/15+12/15)=22 14/15
22 14/15-5 5/6=17 +(28/30-25/30)=17 1/10
3) 17 3/4-9 1/32+4 3/8-5 3/16
17 3/4-5 3/16=12+(12/16-3/16)=12 9/16
-9 1/32+4 3/8= -5+(-1/32+12/32)= -4 21/32
12 9/16-4 21/32=8+(18/32-21/32)=7 29/32
4) 21 4/15+1 5/6- 9 7/30+16 7/24
21 4/15+1 5/6=23+(8/30+25/30)=24 1/10
24 1/10-9 7/30=15 (3/30-7/30)=15-2/15=14 13/15
14 13/15+16 7/24=30+(104/120+35/120)=
31 19/20
1.) 8 1/4 - 2 5/16= 8 4/16 - 2 5/16= 5 15/16
2.) 5 15/ 16 *4/25 = 95/16 * 4/25= 19/20
<span>1) -9(6x+1)=-45(2x+2.6)
-54х-9=-90х-117
-54х+90х=-117+9
36х=-108
х=-3
</span><span>2) 0.6(2x+1)=-1.8(3x-4)
1,2х+0,6=-5,4х+7,2
1,2х+5,4х=7,2-0,6
6,6х=6,6
х=1</span>