Decimal math problems can be confusing and complicated to solve but when you think of decimals in terms of fraction or division, it’s much easier to handle.
To see which number is greater, you may want to divide the number by one and check your answer. Let’s try it with some whole number so it’s easier to understand. For example, to see if the number 2 or 3 is larger, you divide 1/2 or 1/3.
1/2 = .5
1/3 = .33
From these two fractions, you can see that as the denominator increase, the answer decrease. The number 3 is larger than 2 but the answer of .33 is smaller than .5. Knowing this can help you solve your problem.
You can make the two values you have into a fraction/division problem:
1/.834 = 1.200
1/.834224 = 1.199
The answer 1.200 is larger than 1.199 means that the number .834 is smaller than .834224.
If I were teaching this to my students, I would first have them look at the numbers. .83422 has a total of six digits and .834 only has three digits. The student needs to add three zero's to .834 so there are six digits in both numbers. Then have your child look at the numbers similar to how they look at words and put them in alphabetic order. Also have them put the numbers on a time line, which number is bigger? The 8, 3, and 4's are the same, but which is bigger, 2 or 0 (remember, you added the zero to the .832 so that the digits are the same on both numbers.) 2 is bigger, so .834224 is larger.