In a building there are 15 bulbs of $45\mathrm{W},15$ bulbs of $100\mathrm{W},15$ small fans of $10\mathrm{W}$ and 2 heaters of $1\mathrm{k}\mathrm{W}$ . The voltage of electric main is $220\mathrm{V}$ . The minimum fuse capacity (rated value) of the building will be

<p>Total power is <span class="mathml" contenteditable="false"> <math> <mo> (</mo> <mn>15</mn> <mo>*</mo> <mn>45</mn> <mo>)</mo> <mo>+</mo> <mo> (</mo> <mn>15</mn> <mo>*</mo> <mn>100</mn> <mo>)</mo> <mo>+</mo> <mo> (</mo> <mn>15</mn> <mo>*</mo> <mn>10</mn> <mo>)</mo> <mo>+</mo> <mo> (</mo> <mn>2</mn> <mo>*</mo> <mn>1000</mn> <mo>)</mo> <mo>=</mo> <mn>4325</mn> <mtext> </mtext> <mi mathvariant="normal">W</mi> </math> </span>.</p><p>So, current is <span class="mathml" contenteditable="false"> <math> <mfrac> <mrow> <mrow> <mn>4325</mn> </mrow> </mrow> <mrow> <mrow> <mn>220</mn> </mrow> </mrow> </mfrac> <mo>=</mo> <mn>19.66</mn> <mtext> </mtext> <mi mathvariant="normal">A</mi> </math> </span>&lt;!- [endif]-&gt;&lt;!- [endif]-&gt;</p><p>Answer is <span class="mathml" contenteditable="false"> <math> <mn>20</mn> <mi mathvariant="normal">A</mi> <mi mathvariant="normal">m</mi> <mi mathvariant="normal">p</mi> </math> </span>.</p>

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