Let's go through the calculations step by step:

1. Division:
   $1 \div 24 = 0.0416667$ (exact value, without rounding).
   You provided the rounded value: $0.042$, which is close but a rounded form.

2. Multiplication by 21:
   Now, using the exact decimal:
   $0.0416667 \times 21 = 0.875$ (this is the exact value).

   So, multiplying the rounded value $0.042 \times 21 = 0.882$, which is close to the exact result $0.875$, but it's slightly off due to rounding earlier.

Correct Decimal and Fraction:

• Decimal: The precise value is $0.875$, which corresponds exactly to 7/8 as a fraction.
• Fraction: $0.875$ can be written as $\frac{7}{8}$, which simplifies perfectly.

For measurements involving a tablespoon:

• 7/8 tablespoon is very close to 23/25 tablespoons, as 0.88 and 0.875 are almost the same.

Summary:

• The correct exact decimal: $0.875$.
• The correct fraction: $\frac{7}{8}$.

Would you like further details or explanations on this?

Related Questions:

1. How do you convert decimals to fractions?
2. What is the impact of rounding in measurement conversions?
3. How is the value $\frac{7}{8}$ derived from $0.875$?
4. How accurate should measurements be for recipes or precise calculations?
5. Why is it important to use exact values in some situations rather than rounded values?

Tip: For better accuracy, always use the exact decimal value (0.875) before rounding when making precise measurements!