Question

which addition problem is the same as 39 + 60? choose 1 answer: a 3 tens + 6 tens + 9 ones b 3 tens + 9 ones + 6 ones c 3 ones + 6 ones + 9 ones

Explanation:

Step1: Analyze 39 + 60

39 can be broken down into 3 tens (30) and 9 ones (9), and 60 is 6 tens (60). So \(39 + 60=(3\text{ tens}+9\text{ ones})+6\text{ tens}\). Rearranging the terms (since addition is commutative), we get \(3\text{ tens}+6\text{ tens}+9\text{ ones}\).

Step2: Analyze Option A

Option A is \(3\text{ tens}+6\text{ tens}+9\text{ ones}\), which matches the breakdown we did for \(39 + 60\).

Step3: Analyze Option B

Option B is \(3\text{ tens}+9\text{ ones}+6\text{ ones}\). 6 ones is 6, but 60 is 6 tens, not 6 ones, so this does not match \(39 + 60\).

Step4: Analyze Option C

Option C is \(3\text{ ones}+6\text{ ones}+9\text{ ones}\). 39 has 3 tens (not 3 ones) and 60 has 6 tens (not 6 ones), so this does not match \(39 + 60\).

Answer:

A. 3 tens + 6 tens + 9 ones