Answer :

Sure, let's simplify the given expression step-by-step:

Given expression:
[tex]\[ \frac{25 \times t^{-4}}{5^{-3} \times 10 \times t^{-8}} \][/tex]

### Step 1: Simplify the constants

Firstly, simplify the constants in the numerator and denominator independently.

[tex]\[ 25 \quad \text{and} \quad 5^{-3} \times 10 \][/tex]

Recall that [tex]\(5^{-3} = \frac{1}{5^3} = \frac{1}{125}\)[/tex]. Therefore,

[tex]\[ 5^{-3} \times 10 = \frac{1}{125} \times 10 = \frac{10}{125} = \frac{10}{125} = \frac{2}{25} \text{} = 0.4 \][/tex]

Now divide the constant in the numerator, 25, by the constant term [tex]\(0.4\)[/tex]:

[tex]\[ \frac{25}{0.4} = 25 \times 2.5 = 62.5 \][/tex]

In conclusion, the constants simplify to:

[tex]\[ 62.5 \][/tex]

### Step 2: Simplify the exponents of [tex]\(t\)[/tex]

Now we proceed with the variable part of the expression. Recall the properties of exponents:

[tex]\[ \frac{t^{-4}}{t^{-8}} \][/tex]

When dividing terms with the same base, subtract the exponents:

[tex]\[ t^{-4} / t^{-8} = t^{-4 - (-8)} = t^{-4 + 8} = t^{4} \][/tex]

### Step 3: Combine the results

Now combine the simplified constant part with the simplified variable part:

[tex]\[ 62.5 \times t^4 \][/tex]

Therefore, the simplified expression is:

[tex]\[ \boxed{62.5 t^4} \][/tex]

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Summarizing, we've simplified the given expression to:

[tex]\[ \frac{25 \times t^{-4}}{5^{-3} \times 10 \times t^{-8}} = 62.5 t^4 \][/tex]