Question

calculați: a) 2,35+1,8-3,9 b) 3,25+3,(25)-3,2(5)
URGENT!!​

Answer 1

a)

2, 35 + 1, 8 - 3, 9 =

4, 15 - 3, 9 = 0, 25

b)

3, 25 + 3, ( 25 ) - 3, 2 ( 5 ) =

6, 50 ( 25 ) - 3, 2 ( 5 ) = 3, 24 ( 69 )

Answer 2

Răspuns:

Explicație pas cu pas:

a)

2,35 + 1,8 - 3,9 = 0,25

= 4,15 - 3,9 =

= 0,25

__________________

b)

3,25 + 3,(25) - 3,2(5) =

= 325/100 + (325 - 3) / 99 - ( 325 - 32 ) /90 =

= 13/4 + 322/99 - 293/90 =   l  × 1 980

→ c.m.m.m.c al numitorilor (4; 99 si 90) = 4×9×5×11 = 1 980

= ( 13 x 495  + 322 x 20 - 293 x 22 ) / 1 980 =

= ( 6 435 + 6 440 - 6 446 ) / 1 980 =

= ( 12875 - 6446)/1980=

= 6429/1980=

= 3,24(69)