Question

porfavor ayuda porfavor, con procedimiento please
1) 4/9+5/9-2/9=
2) 2/3-5/6+8/9=
3) 1/5-3/10+1/15=
4) 5/4+3/8-7/12=
5) 2/3-3/4+4/5=
6) 5/6-6/7+7/8=
7) 7/6+7/9-7/12=
8) 4/5-9/7+11/15=
9) 11/15-13/18+4/21=
10) 3/2-4/3-2/5=
11) 5/6-7/8+11/12=
12) 6/15*5/18=
13) -24/35(-75/64)=
14) 14/25(-40/49)=
15) 70/143*77/60*13/7=

Answer 1


1) 4/9+5/9-2/9== 9/9- 2/9= 7/9;


2) 2/3-5/6+8/9=(2•6)/(3•6) - (5•3)/(6•3) + (8•2)/(9•2)= 12/18- 15/18+ 16/18= 12/18 + 16/18 - 15/18= 28/18- 15/18= 13/18;


3) 1/5-3/10+1/15= (1•6)/(5•6)- (3•3)/(10•3) + (1•2)/(15•2)= 6/30 - 9/30+2/30= 6/30+ 2/30 -9/30= 8/30 - 9/30= -(9-8)/30= -1/30;


4) 5/4+3/8-7/12= (5•6)/(4•6) + (3•3)/(8•3) - (7•2)/(12•2)= 30/24+ 9/24 - 14/24= 39/24 - 14/24= 25/24= 1 1/24;


5) 2/3-3/4+4/5= (2•20)/(3•20) - (3•15)/(4•15) + (4•12)/(5•12)= 40/60 - 45/60+ 48/60= 40/60+ 48/60 - 45/60= 88/60 - 45/60= 43/60;


6) 5/6-6/7+7/8= (5•28)/(6•28) - (6•24)/(7•24) + (7•21)/(8•21)= 140/168- 144/168+ 147/168= 140/168+ 147/168 - 144/168= 187/168 - 144/168= 43/168;


7) 7/6+7/9-7/12= (7•6)/(6•6)+ (7•4)/(9•4) - (7•3)/(12•3)= 42/36+ 28/36- 21/36= 70/36 - 21/36= 49/36= 1 13/36;


8) 4/5-9/7+11/15= (4• 21)/(5•21)- (9•15)/(7•15)+ (11•7)/(15•7)= 84/105- 135/105+ 77/105= 84/105+ 77/105 - 135/105= 161/105 - 135/105= 26/105;


9) 11/15-13/18+4/21= (11•42)/15- (13•35)/(18•35) + (4•30)/(21•30)= 462/630 - 455/630+ 120/630= 7/630+ 120/630= 127/630;


10) 3/2-4/3-2/5= (3•15)/(2•15)- (4•10)/(3•10)- (2•6)/(5•6)= 45/30 - 40/30- 12/30= 5/30 - 12/30= -( 12-5)/30= -7/30;


11) 5/6-7/8+11/12= (5•12)/(6•12)- (7•9)/(8•9)+ (11•6)/(12•6)= 60/72- 63/72+ 66/72= 60/72+ 66/72 - 63/72= 126/72 - 63/72= 63/72= (63:9)/(72:9)= 7/8;


12) 6/15*5/18= (6:6)/(15:5)• (5:5)/(18:6)= 1/3• 1/3= (1•1)/(3•3)= 1/9;


13) si -24/35• (-75/64)= (24:4)/(35:5)• (75:5)/(64:4)= 6/7• 15/16= (6:2)/7• 15/(16:2)= 3/7• 15/8= 45/56;

Si -24/35(-75/64)= - [24/35+ 75/64)= - [ (24•64)/(35•64)+ (75•35)/(64•35)]= -[1536/2240 + 2625/2240)]= - 4161/2240= -1 1921/2240;


14) si 14/25• (-40/49)= (14:7)/(25:5) • (- (40:5)/(49:7)= 2/5• (-8/7)= - (2•8)/(5•7)= -16/35;

Si 14/25(-40/49)= 14/25- 40/49= (14• 49)/(25•49) - (40•25)/(49•25)= 686/1225- 1000/1225= -(1000-686)/1225= -284/1225;


15) 70/143*77/60*13/7= (70:10)/143• (77:7)/(60:10)• 13/(7:7)= 7/143• 11/6• 13/1= 7/(143:11)• (11:11)/6• 13/1= 7/13• 1/6• 13/1= 7/(13:13)• 1/6• (13:13)/1 = 7/1• 1/6• 1/1 = (7•1•1)/(1•6•1) =
7/6= 1 1/6;