Final answer:
The place values for the digits in 129.3 and 142.7 are 'tens' for the '2' and '4' respectively, and 'ones' for the '9' and '2' respectively, making the correct option D. Tens and ones.
Step-by-step explanation:
The question asks about the place value of the digits in the numbers 129.3 and 142.7. When looking at these numbers, it's important to understand how the place value system works in relation to the decimal point. For the number 129.3, the digit '1' is in the hundreds place, '2' is in the tens place, '9' is in the ones place, and '3' is in the tenths place. For the number 142.7, the digit '1' is in the hundreds place, '4' is in the tens place, '2' is in the ones place, and '7' is in the tenths place. Therefore, the correct answer to the question is 'D. Tens and ones' as these are the place values for the leftmost digits in each number.