[tex]1 \times \frac{3}{4} \times 111.8 \times 860 \\ [/tex]please help me.

The answer is:  " 386 " .
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Explanation:
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Eliminate the "1" ; since "1" multiplied by any value, results in that same value.

We have:

 " (3/4) * (11.8) * (360) " ;

↔  "(3/4) * (360) * (1.8)" ; 

Start with:  "(3/4) * (360)" ; 

→ " (3/4) * (360) =  [tex] \frac{(3*360)}{4} [/tex] ; 

→  The "4" cancels out to a "1" ; and the "360" cancels out to a "90" ; 

→  since:  "(360 ÷ 4 = 90)" ;  and since:  "(4 ÷ 4 = 1)" ; 

And we have:
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→  [tex] \frac{(3 * 90) }{1} = (3 * 90) = 270 [/tex] .

Now, multiply:  "1.8 * 270" ;
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   →     1.8
        *   270
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= (18 * 27) ;  → Take that value and add a "0" to the end of that value; 
   and then: → take "this obtained value" ; and move it back ONE DECIMAL place; 
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   So,   "1.8 * 27 =  ? " ; 
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Step 1)

        ₅
        18 
     * 27
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      126
  + 36
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    3 8 6 
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Step 2:  Add a "0" to the end of that value:
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   "386 " ;  → " 3860 " ; 
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Step 3:  Remove this "obtained value" one decimal place back:
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  "3860" ; → "386.0" ;  write as:  →  " 386 " .
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The answer is:  " 386 " .
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