80 + 10 equals 90 so the missing value is zero, ie 80 + 10 = 90 - 0
The result of the equation - 10 plus 90 plus 60 plus 80, is found as follows; 10 + 90 + 60 + 80 = ( 10 + 90 ) + 60 + 80 = 100 + ( 60 + 80 ) = 100 + 140 = 240 Answer = 240
80+90+100=170+100=270
200
15 + 80/90 = 143/9 = 15.888
80 + 10 equals 90 so the missing value is zero, ie 80 + 10 = 90 - 0
The result of the equation - 10 plus 90 plus 60 plus 80, is found as follows; 10 + 90 + 60 + 80 = ( 10 + 90 ) + 60 + 80 = 100 + ( 60 + 80 ) = 100 + 140 = 240 Answer = 240
80+90+100=170+100=270
390
200
the sum of 80 + 20 + 90 + 10 = 200
15 + 80/90 = 143/9 = 15.888
90
The result of the equation - 130 plus 80 plus 10 plus 80, is found as follows;130 + 80 + 10 + 80= ( 130 + 80 ) + 10 + 80= 210 + ( 10 + 80 )= 210 + 90= 300Answer = 300
ninety 4 + 6 = 10 30 + 50 = 80 10 + 80 = 90 or 56 + 4 = 60 60 + 30 = 90 same as 34 + 6 = 40 40 + 50 = 90
The result of the equation - 90 plus 90 plus 60 plus 80, is found as follows; 90 + 90 + 60 + 80 = ( 90 + 90 ) + 60 + 80 = 180 + ( 60 + 80 ) = 180 + 140 = 320 Answer = 320
-10