Answer:
Natalia's work is wrong.
Step-by-step explanation:
Natalia divided a decimal number by an entire number. Since division is a operation derived from multiplication, the best approach to check if work was good is multiplying the given result by denomination, that is:
1) 
Given.
2) 
Definition of addition.
3) 
Distributive property.
4) 
Definitions of multiplication and decimal number.
5) ![x = 72 +[2\cdot (10)^{-1}]\cdot 12](https://tex.z-dn.net/?f=x%20%3D%2072%20%2B%5B2%5Ccdot%20%2810%29%5E%7B-1%7D%5D%5Ccdot%2012)
Definition of division/Associative property.
6) ![x = 72 + [2\cdot 12]\cdot (10)^{-1}](https://tex.z-dn.net/?f=x%20%3D%2072%20%2B%20%5B2%5Ccdot%2012%5D%5Ccdot%20%2810%29%5E%7B-1%7D)
Associative property.
7) 
Definition of multiplication.
8) 
Definition of divsion.
9) 
Defintion of decimal number.
10) 
Definition of addition/Result
Natalia's work is wrong.
Answer:
the ratio less than 15/24 can be 1:2, 7:8
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