(7,6 - 4 3/4) : 1,9 = 1,5 (или 1 1/2),
1) 7,6 - 4 3/4 = 7,6 - 4 ,75 = 2,85,
2) 2,85 : 1,9 = 1,5,
или:
1) 7,6 - 4 3/4 = 76/10 - 19/4 = 152/20 - 95/20 = 57/20 = 2 17/20),
2) 2 17/20 : 1,9 = 57/20 : 19/10 = 57/20 * 10/19 = 30/20 = 3/2 = 1 1/2)
(2488+4512)*59+(604595-156357):7= 477034
1) 4512+2488=7000
2) 604595-156357=448238
3) 7000*59=413000
4)448238:7=64034
5)413000+64034=477034
1)2 1/2:5 2/3=15/34 2)1 5/26:5 2/3=31/26*3/17= 93/442 3)15/34-93/442 =3/13 4)3 1/2*3/13=7/2*3/13=21/26
√2x+3=3
2x+3=9
2x=9-3
2x=6
x=6:2
x=3