To find 304 - 126, Jill regrouped 30 tens 4 ones as 29 tens 44 ones. What did she do wrong?
304 is 29 tens and 14 ones
Jill regrouped the tens place incorrectly when subtracting 126 from 304. Instead of regrouping 30 tens as 29 tens, she should have regrouped 3 tens as 2 tens and added 10 ones to the ones place.
To figure out what Jill did wrong, let's break down the regrouping process step by step.
First, let's start with the original subtraction problem: 304 - 126.
To regroup, we need to borrow from the tens place (the 0 in 304) to increase the ones place (the 4 in 304).
To borrow, we subtract 1 ten from the 3 tens in the tens place, leaving us with 2 tens.
Now, we take the borrowed ten and add it to the ones place, resulting in 4 ones becoming 14 ones.
So far, our new number looks like this: 294 - 136.
Now we can subtract normally.
Starting from the right, we subtract 6 ones from 14 ones. This gives us 8 ones.
Next, we subtract 2 tens from 9 tens. This gives us 7 tens.
Finally, we combine the tens and ones to get the final answer: 178.
From working through the problem, we can see that Jill made a mistake when regrouping the tens and ones. Instead of correctly regrouping 30 tens and 4 ones as 29 tens and 14 ones, she mistakenly regrouped them as 29 tens and 44 ones.
So, the mistake Jill made was regrouping the ones as 44 instead of 14.