Big Ideas Math: Modeling Real Life, Grade 7
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Exercise 5 Page 273

To write a decimal as a percent, multiply by 100 and add the percent symbol. Construct a 10 * 10 grid to represent this percent.

Percent: 433.3 %
Example Model Representation:

Practice makes perfect

Decimals and percents are ways to show parts of a whole. To write 4.3 as a percent, we multiply by 100 and add the percent symbol %. When doing so, keep in mind that, according to the bar notation, 4.3 is the same as 4.333333.... Let's go!

Percent to decimal
We found that 4.3 expressed as a percent is 433.3333... % or 433.3 %.

Representing the Decimal Using a Model

Now we want to represent 433.3 % with a model. Begin by constructing a 10 * 10 grid — a total of 100 smaller squares. In this grid one square will correspond to 1 % or 0.01. Then the whole square represents 100 %.

Notice that 433.3 % is 433 and 0.3 parts out of 100 parts. Since 0.3 is equivalent to 13, we will color 433 and a third of a small square. <jsxgpre id="Solution_269083_3" alt="Model" static=0> var b = mlg.board([-2.5, 26.5, 38.5, -10], {

 desktopSize: "medium",
 style: "usa"

}); var bb = b.board.getBoundingBox(); var buttons = []; var labs = ["Reset", "Color the Squares"];

var n1 = b.node(0, 0 + 6.5); var n2 = b.node(0, 10 + 6.5); var n3 = b.node(10, 10 + 6.5); var n4 = b.node(10, 0 + 6.5);

var n5 = b.node(13, 0); var n6 = b.node(13, 10); var n7 = b.node(23, 10); var n8 = b.node(23, 0);

var n9 = b.node(13 + 13, 0); var n10 = b.node(13 + 13, 10); var n11 = b.node(23 + 13, 10); var n12 = b.node(23 + 13, 0);

var n13 = b.node(13, 0 + 13); var n14 = b.node(13, 10 + 13); var n15 = b.node(23, 10 + 13); var n16 = b.node(23, 0 + 13);

var n17 = b.node(13 + 13, 0 + 13); var n18 = b.node(13 + 13, 10 + 13); var n19 = b.node(23 + 13, 10 + 13); var n20 = b.node(23 + 13, 0 + 13);

var pol1 = b.polygon([n1, n2, n3, n4], {

 borders: { strokeColor: "darkviolet", opacity: 0.3 }

}); var pol2 = b.polygon([n5, n6, n7, n8], {

 borders: { strokeColor: "darkviolet", opacity: 0.3 },
 color: "darkorange",
 opacity: 0.5

}); var pol3 = b.polygon([n9, n10, n11, n12], {

 borders: { strokeColor: "darkviolet", opacity: 0.3 },
 color: "darkorange",
 opacity: 0.5

}); var pol4 = b.polygon([n13, n14, n15, n16], {

 borders: { strokeColor: "darkviolet", opacity: 0.3 },
 color: "darkorange",
 opacity: 0.5

}); var pol5 = b.polygon([n17, n18, n19, n20], {

 borders: { strokeColor: "darkviolet", opacity: 0.3 },
 color: "darkorange",
 opacity: 0.5

});

var L = 11; /*Grid 1*/ var sp1 = b.segmentPoints(pol1.borders[0], L, { visible: false }); var sp2 = b.segmentPoints(pol1.borders[1], L, { visible: false }); var sp3 = b.segmentPoints(pol1.borders[2], L, { visible: false }); var sp4 = b.segmentPoints(pol1.borders[3], L, { visible: false }); for (var i = 1; i < sp1.length - 1; i++) {

 b.segment(sp1[i], sp3[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });
 b.segment(sp2[i], sp4[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });

}

/*Grid 2*/ var sp11 = b.segmentPoints(pol2.borders[0], L, { visible: false }); var sp21 = b.segmentPoints(pol2.borders[1], L, { visible: false }); var sp31 = b.segmentPoints(pol2.borders[2], L, { visible: false }); var sp41 = b.segmentPoints(pol2.borders[3], L, { visible: false }); for (var i = 1; i < sp1.length - 1; i++) {

 b.segment(sp11[i], sp31[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });
 b.segment(sp21[i], sp41[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });

}

/*Grid 3*/ var sp111 = b.segmentPoints(pol3.borders[0], L, { visible: false }); var sp211 = b.segmentPoints(pol3.borders[1], L, { visible: false }); var sp311 = b.segmentPoints(pol3.borders[2], L, { visible: false }); var sp411 = b.segmentPoints(pol3.borders[3], L, { visible: false }); for (var i = 1; i < sp1.length - 1; i++) {

 b.segment(sp111[i], sp311[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });
 b.segment(sp211[i], sp411[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });

} /*Grid 4*/ var sp1111 = b.segmentPoints(pol4.borders[0], L, { visible: false }); var sp2111 = b.segmentPoints(pol4.borders[1], L, { visible: false }); var sp3111 = b.segmentPoints(pol4.borders[2], L, { visible: false }); var sp4111 = b.segmentPoints(pol4.borders[3], L, { visible: false }); for (var i = 1; i < sp1.length - 1; i++) {

 b.segment(sp1111[i], sp3111[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });
 b.segment(sp2111[i], sp4111[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });

}

/*Grid 5*/ var sp11111 = b.segmentPoints(pol5.borders[0], L, { visible: false }); var sp21111 = b.segmentPoints(pol5.borders[1], L, { visible: false }); var sp31111 = b.segmentPoints(pol5.borders[2], L, { visible: false }); var sp41111 = b.segmentPoints(pol5.borders[3], L, { visible: false }); for (var i = 1; i < sp1.length - 1; i++) {

 b.segment(sp11111[i], sp31111[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });
 b.segment(sp21111[i], sp41111[L - 1 - i], {
   strokeWidth: 1,
   strokeColor: "blue",
   opacity: 0.3
 });

}

var Rec = []; for (var j = 1; j < 4; j++) {

 for (var i = 0; i < L - 1; i++) {
   Rec.push(
     b.rectangle(
       b.node(sp2[j - 1].X(), sp1[i].Y()),
       b.node(sp2[j].X(), sp1[i + 1].Y()),
       {
         fillColor: "darkorange",
         fillOpacity: 0.5,
         borders:{visible:false},
         visible: false
       }
     )
   );
 }

} Rec.push(

 b.rectangle(b.node(sp2[3].X(), sp1[0].Y()), b.node(sp2[4].X(), sp1[1].Y()), {
   fillColor: "darkorange",
   fillOpacity: 0.5,
   borders:{visible:false},
   visible: false
 })

); Rec.push(

 b.rectangle(b.node(sp2[3].X(), sp1[1].Y()), b.node(sp2[4].X(), sp1[2].Y()), {
   fillColor: "darkorange",
   fillOpacity: 0.5,
   borders:{visible:false},
   visible: false
 })

); Rec.push(

 b.rectangle(b.node(sp2[3].X(), sp1[2].Y()), b.node(sp2[4].X(), sp1[3].Y()), {
   fillColor: "darkorange",
   fillOpacity: 0.5,
   borders:{visible:false},
   visible: false
 })

); Rec.push(

 b.rectangle(
   b.node(sp2[3].X(), sp1[3].Y()),
   b.node(sp2[4].X(), sp1[3].Y() + 1 / 3),
   {
     fillColor: "darkorange",
     fillOpacity: 0.5,
     borders:{visible:false},
     visible: false
   }
 )

);

/*animation*/ var per1 = b.segmentText(pol1.borders[3], {

 name: "0\\%",
 color: "darkorange",
 distance: 1.5

}); var per2 = b.segmentText(pol2.borders[3], {

 name: "100\\%",
 color: "darkorange",
 distance: 1.5

}); var per3 = b.segmentText(pol3.borders[3], {

 name: "100\\%",
 color: "darkorange",
 distance: 1.5

}); var per4 = b.segmentText(pol4.borders[1], {

 name: "100\\%",
 color: "darkorange",
 distance: 1.5

}); var per5 = b.segmentText(pol5.borders[1], {

 name: "100\\%",
 color: "darkorange",
 distance: 1.5

});

var f1 = b.polarnode(n1, -90, 2 + 6.5); var f2 = b.polarnode(n12, -90, 2); var Per = b.curlyBrace(f2, f1, {

 strokeWidth: 1,
 label: { text: "400\\%\\text{ or } 4.00", distance: 0, color: "darkorange" }

});

var count = 0; var F1 = function () {

   var interval = setInterval(function () {
     b.setAttribute(Rec[count], { visible: true, transitionDuration: 250 });
     count++;
     if (count > Rec.length) {
       clearInterval(interval);
       buttons[0].enable();
       buttons[0].setLabel(labs[0]);
       buttons[0].setDimension(60, 30);
       b.changeText(per1.text, "33.\\bar{3}\\%");
       b.changeText(Per.label,"433.\\bar{3}\\% \\text{ or }4.\\bar{3}");
     } else {
         if(count<=33){
               b.changeText(per1.text, count + "\\%");
               b.changeText(Per.label,400 + count + "\\% \\text{ or }" + b.round((400 + count) / 100, 2));
         }
     }
   }, 250);
 };

var F2 = function () {

 b.setAttribute(Rec, { visible: false });
 count = 0;
 b.changeText(per1.text, count + "\\%");
 b.changeText(
   Per.label,
   400 + count + "\\% \\text{ or }" + b.round((200 + count) / 100, 2)
 );
 buttons[0].enable();
 buttons[0].setLabel(labs[1]);
 buttons[0].setDimension(125, 30);

};

var kk = 0; var button = function () {

 buttons[0].disable();
 if (kk % 2 == 0) {
   F1();
 } else {
   F2();
 }
 kk++;

};

buttons.push(

 b.button(0.5 * (bb[0] + bb[2]), bb[3] + 0.5, labs[1], button, {
   mathMode: false,
   width: 125,

anchor: "s"

 })

);

</jsxgpre>