Hey!
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Question B:
12 tenths + 9 tenths
~Turn into decimal
1.2 + 0.9
~Add
1.2 + 0.9 = 2.1
~Answer
one(s): 2
tenth(s): 1
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Question C:
3 hundredths + 4 hundredths
Turn into decimal
0.03 + 0.04
~Add
0.03 + 0.04 = 0.07
~Answer
hundredth(s): 7
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Hope This Helped! Good Lucked!