Posts Tagged ‘math’

SAT test & Calculator

Wednesday, January 27th, 2010

There has been a lot of debate over using calculator in the SAT test. And the good news is that you should definitely make use of the calculator. After all, you take the SAT to get good scores and get admitted in your favorite college, and to show off your mental calculation skills.

The SAT test, as well all know, tests our reasoning skills. The Math section contains questions of different difficulty levels. While you might feel the need to use a calculator for simple questions, problems that involve lengthy calculations might eat up your time if you do not use a calculator.

calculator_necessity

When to use the calculator? If you are good at math, and you can do basic arithmetic in your head, you are lucky. However, if math problems do trouble you, using a calculator would be a good decision.  Again, the same problem can attract use of calculator in different ways.

To give an example, let us see how a math problem can be solved in different ways using a calculator, and without it too.

If 16 × 25 × 36 = (4a) 2 Find a

Options: (A) 6     (B) 15     (C) 30     (D) 36     (E) 60

Approach 1: Too much use of calculator

Calculate 16 × 25 × 36 = 14400

See that (4a) 2 = 16a2

So, 16a2 = 14400

Use the calculator to divide 14400 with 16 to get a2 = 900

Again use the calculator to find the Square root of 900. Therefore, a = 30

Approach 2: Little use of calculator

16 × 25 × 36 = 16a2

The 16 on LHS can be cancelled with the 16 on the RHS

Multiply 25 x 36 using a calculator to get 900

So we get 900 = a2

Take the square root of 900 using the calculator. So the answer is a = 30

Smart Approach: No Calculator

Cancel the 16 on both side of the equation.

Also note that 25 x 36 = a2 can be written as 52 x 62 = a2

Hence a = 30

Geometry the Fun Way: Congruence

Thursday, December 24th, 2009

How often do teachers try to teach mathematical concept using objects used in our day-to-day lives? Research has shown that children understand things better when they are taught using images and objects that they see and use. Though most educators and parents know this, not many really implement this to educate children.

Take for instance, congruence of triangles. I am use most teachers would use the following images to teach ‘congruence’ to children.

congruence

The problem with these images is that children might not take interest in understanding the concepts as they do not find ‘fun’ in these.  While these images are good for senior students, a beginner in geometry might fail to understand the meaning of ‘congruence’.

However, the same can be taught in an interesting fashion.

congruence_scissors

congruence_closed

Online tutoring is a great way of teaching children using images and pictures. Modern tools like the whiteboard allow online tutors to import images and even change their alignment to teach a concept to children.  Online math tutors, in particular, can use images used in our day-to-day lives to teach mathematical concept to K-12 students in an interesting way.

Geometry in Real Life

Thursday, December 24th, 2009

In general, whenever we are stuck solving a problem or understanding a concept, we think to ourselves “This is sheer waste of time. Am I going to use this in real life?” I agree that for most subjects, only the core elements are used in real life and not the details. However, there is one aspect of mathematics that will come across in varied forms in real life. You guessed it right, I am talking about Geometry.

Let us talk about some of the practical aspects of geometry that we, often unknowingly, use in real life over and over again. Christmas has almost arrived. Most of us would be busy decorating our homes with Christmas trees and bells. But before buying a Christmas tree, don’t we first try to determine its size that would fit in our drawing room through the main door? In other words, we determine the width and height of the tree. And that’s geometry, isn’t it?

geometry

The same goes with an architect who is about to develop a construction plan for a new building. Cooking is no different. When we bake a cake in a microwave-safe bowl, we determine the quantity that would fit in the bowl.  There are hundreds of examples that demonstrate geometry into action in our day to day lives.

Geometry can be made fun. Online Tutoring organizations can conduct workshops on teaching geometry to children using day-to-day objects. Geometry is an essential part of online math tutoring. An online geometry tutor would not only help children understand the concepts given in their school books, but also learn to apply those concepts in real life without getting bored.

Why do we need Math?

Saturday, December 12th, 2009

In the words of Albert Einstein “Education is what remains after one has forgotten what one has learned in school”.

Teachers come across some so called ‘rebels’ in school who ask questions like ‘Why do we need to learn Math?’ or ‘what good would this do when we grow up?’. While most teachers would talk about (more…)