simple03.html

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title: Simple HTML - Doing sums
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		<h1>Doing sums</h1>
		<p>The command <code class="command">PRINT</code>, followed by a sum, tells the computer to work out the sum and put the answer on
			the screen. Try the <code class="command">PRINT</code> commands shown below. The commands have no line
			numbers, so the computer carries out each one straight away.</p>
<pre>
PRINT 2+2
PRINT 2*3
PRINT 6/2
PRINT 2-4
</pre>
		<center><img src="{{ base_uri }}/img/usborne/simple-basic/img/04sums.jpg"></center>

		<h2>Hours program</h2>
		<p>This program makes the computer
			work out the number of hours in a year.
			Line 30 does the calculation. It multiplies the number of days in a year, by the number of hours in a day.</p>
		<p>Let’s type it in and <code class="command">RUN</code> it now.</p>
<pre>
NEW
10 CLS
20 PRINT "THERE ARE "
30 PRINT 365*24
40 PRINT "HOURS IN"
50 PRINT " A YEAR"
RUN
</pre>
		<center><img src="{{ base_uri }}/img/usborne/simple-basic/img/04hours.jpg"></center>

		<p>Notice that there are spaces in the strings we're printing above, which look like they're intended for the message
			to be printed out on one line, but because <code class="command">PRINT</code> outputs on a new line, the spaces
			aren't really necessary.
		</p>
		<p>You can modify a <code class="command">PRINT</code> so it doesn't end with a new line by putting a semicolon after it. Try editing
		your program using <code class="command">EDIT</code> followed by a line number, to add semicolons to the end of lines 
		20, 30 and 40, then run it again.</p>
		<p>Your code should end up looking like this:</p>
<pre>
10 CLS
20 PRINT "THERE ARE ";
30 PRINT 365*24;
40 PRINT "HOURS IN";
50 PRINT " A YEAR"
</pre>

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