document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1210646>Question 1210646</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Concrete blocks of length (14/25)m were laid end to end along the four sides of a rectangular lawn 28 m long and 21 m wide. <BR>\n" );
document.write( "(a) How many blocks were required to complete one layer?<BR>\n" );
document.write( "(b) If each block costs GH¢1.80 and the cost of labour is one-third the cost of a block, find the total cost of laying the blocks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #854707 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5398)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=854707\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> WHAT THE TEACHER PROBABLY EXPECTS:<BR>\n" );
document.write( "(a) How many blocks were required to complete one layer?<BR>\n" );
document.write( "Calculate the perimeter like the teacher showed in class.<BR>\n" );
document.write( "If the teacher expects you to write a formula, such as <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Perimeter=2%28length%2Bwidth%29 ALIGN=MIDDLE  ALT=\"Perimeter=2%28length%2Bwidth%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > , write the formula the teacher provided.<BR>\n" );
document.write( "Otherwise, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Perimeter=28m%2B21m%2B28m%2B21m=98m ALIGN=MIDDLE  ALT=\"Perimeter=28m%2B21m%2B28m%2B21m=98m\"   DISABLED_style= \"max-width:90%; height:auto;\" > will  probably do.<BR>\n" );
document.write( "Then divide that length by the length of a block to find the number of blocks:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=98%2F%2214+%2F+25%22=98%2A%2825%2F14%29=highlight%28175%29 ALIGN=MIDDLE  ALT=\"98%2F%2214+%2F+25%22=98%2A%2825%2F14%29=highlight%28175%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <BR>\n" );
document.write( "b) If each block costs GH¢1.80 and the cost of labour is one-third the cost of a block, find the total cost of laying the blocks.<BR>\n" );
document.write( "The cost of the blocks, in GH¢, is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1.80%2A175=315 ALIGN=MIDDLE  ALT=\"1.80%2A175=315\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "THe cost of the labour is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315%2F3=105 ALIGN=MIDDLE  ALT=\"315%2F3=105\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "Total cost, in GH¢, is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=315%2B105=highlight%28420%29 ALIGN=MIDDLE  ALT=\"315%2B105=highlight%28420%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <BR>\n" );
document.write( "THE REAL-LIFE PROBLEM:<BR>\n" );
document.write( "In real life, things are not so simple, and we do not know many details of how exactly to do this job.<BR>\n" );
document.write( "There are many questions.<BR>\n" );
document.write( "(a) the number of blocks were required to complete one layer:<BR>\n" );
document.write( "With all lengths in m, the ratio of lengths is the number of blocks required to fill one length:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=28%2F%2814%2F25%29=28%2A25%2F14=2%2A25=highlight%2850%29 ALIGN=MIDDLE  ALT=\"28%2F%2814%2F25%29=28%2A25%2F14=2%2A25=highlight%2850%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Is that what was called \"one layer\"?<BR>\n" );
document.write( "with <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2A50blocks=100blocks ALIGN=MIDDLE  ALT=\"2%2A50blocks=100blocks\"   DISABLED_style= \"max-width:90%; height:auto;\" > we get a line of blocks 28 m long along each long edge.<BR>\n" );
document.write( "Getting a line of blocks along one 21-m width with blocks would be the ratio of lengths:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=21%2F%2814%2F25%29=21%2A25%2F14=%2821%2F14%29%2A25=%283%2F2%29%2A25=75%2F2=37.5 ALIGN=MIDDLE  ALT=\"21%2F%2814%2F25%29=21%2A25%2F14=%2821%2F14%29%2A25=%283%2F2%29%2A25=75%2F2=37.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > ,<BR>\n" );
document.write( "so the number of blocks required to line the 2 widths would be<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2A%2875%2F2%29=75 ALIGN=MIDDLE  ALT=\"2%2A%2875%2F2%29=75\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "However, the devil is in the details.<BR>\n" );
document.write( "How exactly are we lining that rectangular lawn, and how wide are those blocks?<BR>\n" );
document.write( "Are they placed just along the outside, like this:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28400%2C300%2C-4%2C32%2C-3%2C24%2C%0D%0Agreen%28rectangle%280.1%2C0.1%2C27.9%2C20.9%29%29%2C%0D%0Arectangle%280%2C0%2C28%2C-0.5%29%2Crectangle%280%2C21%2C28%2C21.5%29%2C%0D%0Arectangle%280%2C0%2C-0.5%2C21%29%2Crectangle%2828%2C0%2C28.5%2C21%29%2Clocate%2813%2C21%2Cgreen%2828m%29%29%2C%0D%0Alocate%280.2%2C12%2Cgreen%2821m%29%29%2Clocate%2813%2C12%2Cgreen%28lawn%29%29%2C%0D%0Alocate%2811%2C24%2C50%29%2Clocate%2813%2C24%2Cblocks%29%2C%0D%0Aarrow%2812.5%2C23%2C12.5%2C21.2%29%2Clocate%2829%2C24%2C37.5%29%2Clocate%2828.2%2C23%2Cblocks%29%2C%0D%0Aarrow%2830.1%2C21.5%2C28.3%2C16%29%0D%0A%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%3F%22 ALIGN=MIDDLE  ALT=\"%22%3F%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "My drawing show how it would look in a photo taken with a drone.<BR>\n" );
document.write( "Lining all 4 sides as shown in the design will require<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=100blocks%2B75blocks=highlight%28175blocks%29 ALIGN=MIDDLE  ALT=\"100blocks%2B75blocks=highlight%28175blocks%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Lining the inside edges would take less blocks because the rectangles in my drawing would be inside the lawn and would overlap at the corners.<BR>\n" );
document.write( "If we put the blocks outside as in my drawing, do we have to fill completely or partially those empty corners?<BR>\n" );
document.write( "Are those blocks sold by the block or in packages of 100?<BR>\n" );
document.write( "Should we buy more blocks to fill corners, or because blocks could break accidentally, or when trying to cut them in half?<BR>\n" );
document.write( "What is the width of those blocks? It would matter if we have to fill those corners in my drawing.<BR>\n" );
document.write( "The width of the blocks in my drawing is 1/2 m, and their height is not visible,<BR>\n" );
document.write( "because we are looking from high above. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );