Question

afla nr.necunoscute:
45:a X 100=900
25X4:a=20
824-240:a=800
245+50Xa=745
a:9X8=808
aX6:9=32

Answer 1

45: a ×100= 900 45: a= 900:100 a= 45: 9 a= 5

Answer 2

45:a*100=900
45:a=90:100
45:a=9
a=45:9
a=5

25*4:a=20
100:a=20
a=100:20
a=5

824-240:a=800
824-800=240*a
24=240a
a=240:24
a=10

245+50*a=745
50*a=745-245
50a=500
a=500:50
a=10

a:9*8=808
a:9=808:8
a:9=101
a=101*9
a=909

a*6:9=32
a*6==32*9
a*6=288
a=288:6
a=48