Answer:
a:b = 6:10 = 3:5 = 21:35
b:c = 21:33 = 7:11 = 35:55
a:b:c = 21:35:55
You have to make sure that whatever you do to one side, you also do to the other.
2x + 37 = 8x + 7
2x + 37 - 2x = 8x + 7 - 2x
37 = 6x + 7
37 - 7 = 6x + 7 - 7
30 = 6x
30 / 6 = 6x / 6
5 = x
x = 5
Hope this helps! :)
Remark
This is an excellent question. Estimation is a powerful skill to have. People should always shop using estimates. Try it to see what happens.
x = 11.7 which rounds up to which we will call x1 and that is 12
y = 6.03 which round down to 6 which we will call y1 and that is 6
Now x - y = 5.67
If you do the rounded subtraction x1 - y1 = 12 - 6 = 6
The estimate is not zero. D is not correct.
There is enough information E is not the answer.
B is wrong, her estimate is larger than x - y
C is wrong the two subtractions are not equal.
A is correct and always will be no matter what numbers are chosen
A <<<< Answer