**Modeling percent problems :**

To have better understanding of solving real world problems involving percent, we can use a model.

Let us see how models can be used too solve percent problems.

A sports store received a shipment of 400 baseball gloves. 30% were left-handed. How many left-handed gloves were in the shipment ?

**Question (i) :**

Complete the diagram to model this situation.

**Answer :**

**Question (ii) :**

What does 30% mean ?

**Answer :**

30 % means 30 out of 100.

**Question (iii) :**

How many left-handed gloves were there for every 100 baseball gloves ?

**Answer :**

There were 30 left-handed gloves were there for every 100 baseball gloves.

**Question (iv) :**

Describe how the diagram models the shipment of gloves.

**Answer : **

One large rectangle represents 100 gloves so 4 rectangles represent 400 gloves. One small rectangle represents 30 out of 100 gloves that are left-handed.

**Question (v) :**

Explain how you can use the diagram to find the total number of left-handed gloves in the shipment.

**Answer : **

There were 30 left-handed gloves in each 100 baseball gloves.

To find the total number of left handed gloves, we have to add the 30s in all the four parts.

So, we have

30 + 30 + 30 + 30 = 120

**Question (vi) :**

Use a bar model to solve this problem. The bar represents 100%, or the entire shipment of 400 gloves. The bar is divided into 10 equal parts. Complete the labels along the bottom of the bar.

**Answer :**

**Question (vii) :**

How did you determine the labels along the bottom of the bar model in question (v) ?

**Answer :**

The bar shows 400 divided into 10 equal parts, so each part represents 400 ÷ 10 = 40.

That is, for every 10% increase at the top, there is an increase of 40 at the bottom.

Based on this fact, we can complete the labels along the bottom of the bar

0% = 0

10% = 40 <--------(0 + 40)

20% = 80 <--------(40 + 40)

30% = 120 <--------(80 + 40)

40% = 160 <--------(120 + 40)

50% = 200 <--------(160 + 40)

60% = 240 <--------(200 + 40)

70% = 280 <--------(240 + 40)

80% = 320 <--------(280 + 40)

90% = 360 <--------(320 + 40)

100% = 400 <--------(360 + 40)

**Question (viii) :**

How can you use the bar model to find the number of left-handed gloves ?

**Answer :**

30% of 400 = (30/100) x 400

30% of 400 = 30 x 4

30% of 400 = 120

There were 120 left-handed gloves.

After having gone through the stuff given above, we hope that the students would have understood "Modeling percent problems".

Apart from the stuff given above, if you want to know more about "Modeling percent problems", please click here

Apart from the stuff given in this section, if you need any other stuff in math, please use our google custom search here.

HTML Comment Box is loading comments...

**WORD PROBLEMS**

**HCF and LCM word problems**

**Word problems on simple equations **

**Word problems on linear equations **

**Word problems on quadratic equations**

**Area and perimeter word problems**

**Word problems on direct variation and inverse variation **

**Word problems on comparing rates**

**Converting customary units word problems **

**Converting metric units word problems**

**Word problems on simple interest**

**Word problems on compound interest**

**Word problems on types of angles **

**Complementary and supplementary angles word problems**

**Markup and markdown word problems **

**Word problems on mixed fractrions**

**One step equation word problems**

**Linear inequalities word problems**

**Ratio and proportion word problems**

**Word problems on sets and venn diagrams**

**Pythagorean theorem word problems**

**Percent of a number word problems**

**Word problems on constant speed**

**Word problems on average speed **

**Word problems on sum of the angles of a triangle is 180 degree**

**OTHER TOPICS **

**Time, speed and distance shortcuts**

**Ratio and proportion shortcuts**

**Domain and range of rational functions**

**Domain and range of rational functions with holes**

**Graphing rational functions with holes**

**Converting repeating decimals in to fractions**

**Decimal representation of rational numbers**

**Finding square root using long division**

**L.C.M method to solve time and work problems**

**Translating the word problems in to algebraic expressions**

**Remainder when 2 power 256 is divided by 17**

**Remainder when 17 power 23 is divided by 16**

**Sum of all three digit numbers divisible by 6**

**Sum of all three digit numbers divisible by 7**

**Sum of all three digit numbers divisible by 8**

**Sum of all three digit numbers formed using 1, 3, 4**

**Sum of all three four digit numbers formed with non zero digits**