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If a, b, and c are digits for which the following holds, then a +b+c= 9 a 1-7 2 b= c 8 2a+b+c=

If a, b, and c are digits for which the following holds, then a +b+c= 9 a 1-7 2 b-example-1
User Lindell
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2 Answers

2 votes

The sum of the digits
\( a \),
\( b \), and
\( c \) is
14.

The image appears to show a column addition problem with missing digits represented by a, b, and c:

9 a 1

+ 7 2 b

------------

c 8 2

To solve this, we follow the standard procedure for addition, starting from the rightmost column:

1. In the rightmost column,
\( b + 1 \) must equal 2, or result in 2 when 10 is subtracted (if there's a carry-over from the middle column). Since there's no carry-over mentioned, and b is a single digit,
\( b = 1 \).

2. In the middle column,
\( a + 2 \) must give us the units digit of 8. Since
\( b = 1 \), and there's no carry-over from the rightmost column,
\( a \) must be 6 to make
\( 6 + 2 = 8 \).

3. In the leftmost column, we add 9 and 7 to get 16. The digit 'c' in the sum must be 1 more than the 10's place of this sum due to the carry-over from the middle column (if any). Since 9 + 7 = 16, there is a carry-over, and so
\( c = 6 + 1 = 7 \).

Now we can sum a, b, and c:


\( a + b + c = 6 + 1 + 7 \)

Calculating this, we get:

The sum of the digits
\( a \),
\( b \), and
\( c \) is
14.

User John Hoven
by
4.5k points
5 votes

Answer:

11

Step-by-step explanation:

Given the difference:


\begin{gathered} \; \; 9\text{ a 1} \\ -7\text{ 2 b} \\ ---- \\ \; \; c\text{ 8 2} \end{gathered}
\begin{gathered} 11-9=2 \\ \text{Therefore, b=9} \end{gathered}
\begin{gathered} 10-2=8 \\ 10+1=11 \\ \text{Therefore, a=1} \end{gathered}

Lastly:


\begin{gathered} (9-1)-7=1 \\ \text{Therefore: c=1} \end{gathered}

We then have:


\begin{gathered} \; \; 9\text{ 1 1} \\ -7\text{ 2 }9 \\ ---- \\ \; \; 1\text{ 8 2} \end{gathered}

Therefore:

a+b+c=9+1+1=11

User Olivier
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5.6k points