add 3_--21 + 7_--21.

_--24 + _--28
10_--21
10_--42
_--52

1 answer

To solve the expressions involving the numbers with bases in the form of __--21, __--24, __--28, __--42, and __--52, we need to follow these steps:

  1. Convert the numbers from their respective bases to decimal.
  2. Perform the arithmetic operations.
  3. Convert the result back to the required base if necessary.

Let's break this down.

Step 1: Base Conversion

Let's assume the numbers are written as follows:

  • 3_--21: This is a number in base 21.
  • 7_--21: This is another number in base 21.

In base b, the number 3_b represents \(3 \times b^0 = 3\) in decimal. Similarly, for 7_b, it represents \(7 \times b^0 = 7\).

So:

  • \(3_{21} = 3\)
  • \(7_{21} = 7\)

Now we perform addition of these two numbers:

\[ 3 + 7 = 10 \]

Now we recognize that \(10_{21}\) still means the same \(10\) when viewed, but the number is the same in decimal.

Step 2: Second Part of the Expression

Now let's evaluate:

\(_--24 + _--28\)

Here we don’t have specific numbers to work with in those bases. However, from the previous step, we assume they are summations awaiting specific base interpretations.

Suppose the results represent a range of numbers in other bases not fully specified: Yet we can structure this numeral placement.

Step 3: Evaluating Other Expressions

For the numbers:

  • \(10_{21} = 10_{21}\) remains 10.

  • \(10_{42}\): This too means \(10_{42}=10\).

Lastly for \(_--52\), this notation isn't specific, yet retains the general number scheme.

Conclusion:

Since we lack distinct numbers for parts of the second equation and thus cannot render a direct solution for it, we can resolve the equations we clearly interpret:

  • Therefore, \(3_--21 + 7_--21 = 10_{21}\)
  • And \(10_{42}\) = 10.

The _--52 remains unspecified for proper numeric context but might lead to characteristic values in numeral specifications based on exact computation needed for clarity.

If you can provide additional information or a specific number in the formats indicated, I can offer a more precise resolution!