Question

the digit 9 in which number represents a value of 90?
choose 1 answer:
a 95
b 953
c 729

Explanation:

Step1: Analyze the place value of 9 in each option.

• For option A (95): The digit 9 is in the tens place? No, wait, 95 is a two - digit number. The place value of 9 in 95 is $9\times10 = 90$? Wait, no, 95 has 9 in the tens place? Wait, 95 is 9 tens and 5 ones. Wait, 9 tens is $9\times10=90$? Wait, no, 9 in 95 is in the tens place? Wait, 95 is a two - digit number, the left - most digit is the tens place. So 9 in 95 is in the tens place? Wait, no, 95 is 9 tens and 5 ones. Wait, 9 tens is 90? Wait, no, 9 in 95: 9 is in the tens place? Wait, 95 is 910 + 51=95. So the place value of 9 in 95 is 90? Wait, no, wait 95 is a two - digit number, the first digit (9) is in the tens place? Wait, no, in a two - digit number, the left digit is the tens place. So 9 in 95: place value is 9*10 = 90? Wait, but let's check other options.
• For option B (953): The digit 9 is in the hundreds place. The place value of 9 is $9\times100 = 900$.
• For option C (729): The digit 9 is in the ones place. The place value of 9 is $9\times1=9$.

Wait, wait, I made a mistake earlier. Wait, 95 is a two - digit number. The digits are: the right - most digit is the ones place, the left - most (for two - digit) is the tens place. So in 95, 9 is in the tens place? Wait, no, 95: 9 is in the tens place? Wait, 910+51 = 95. So the place value of 9 in 95 is 90? Wait, but let's re - check.

Wait, option A: 95. The digit 9 is in the tens place? Wait, no, 95 is 9 tens and 5 ones. So 910 = 90. Option B: 953, 9 is in the hundreds place, 9100 = 900. Option C: 729, 9 is in the ones place, 9*1 = 9. So the digit 9 in 95 has a place value of 90. Wait, but the option A is 95. Wait, but let's confirm the place values.

Place value: In a number, the place of a digit determines its value. For a number with digits $d_{n}d_{n - 1}\cdots d_{1}d_{0}$, the place value of $d_{i}$ is $d_{i}\times10^{i}$.

• For 95: digits are 9 (tens place, $i = 1$) and 5 (ones place, $i = 0$). So place value of 9 is $9\times10^{1}=90$.
• For 953: digits are 9 (hundreds place, $i = 2$), 5 (tens place, $i = 1$), 3 (ones place, $i = 0$). Place value of 9 is $9\times10^{2}=900$.
• For 729: digits are 7 (hundreds place, $i = 2$), 2 (tens place, $i = 1$), 9 (ones place, $i = 0$). Place value of 9 is $9\times10^{0}=9$.

So the digit 9 in 95 has a place value of 90. Wait, but the option A is 95. Wait, but let's check the options again. The options are A. 95, B. 953, C. 729. So the correct answer is A? Wait, but wait, 95: 9 is in the tens place? Wait, no, 95 is a two - digit number, the first digit (9) is in the tens place? Wait, no, in a two - digit number, the left digit is the tens place. So 9 in 95 is in the tens place, so its place value is 9*10 = 90. So the answer is A.

Answer:

A. 95