Spending Time  You do it every day. You barely give it a second thought. Yet, if you do it as you've been instructed, you will spend more than a day each year do it. What is it?  Hint
Solution The Math 
Ratio and Proportion Machines  There are a few ratio and proportion machines in your home. What are they?  Hint
Solution The Math 
Adding Car Lane  You
are stuck in rushhour traffic. All the highway lanes are packed. What
if they add another lane, by how much will it reduce the traffic load on
each existing lane?

Hint
Solution The Math 
Spending Time  You do it every day  Puzzle
Solution The Math 
Ratio and Proportion Machines  You use it every day, many times. It is up to you whether it is a ratio machine or a proportion machine. Sometimes both.  Puzzle
Solution The Math 
Adding Car Lane  Say
there are now three lanes, what if they added a fourth one?

Pazzle
Solution The Math 
Spending Time  Brusing your teeth.  Puzzle
Hint
The Math 
Ratio
and Proportion Machines

The hot and cold water faucets in kitchens and bathrooms...  Puzzle
Hint The Math 
Adding Car Lane  By
one fourth of the current traffic load.

Pazzle
Hint The Math 
Spending Time  If
you brush your teeth twice daily for two minutes each time, each year you
will spend

Puzzle
Hint Solution 
Ratio and Proportion Machines  The
hot and cold water faucets in kitchens and bathrooms adjust the ratio of
hot and cold water in the mix and that comes out of the spout. Once you
like the temperature of the mix, adjusting the flow, you maintain the hottocold
ratio. In other words, you preserve the proportion.
If you have a faucet with a singlelever control then in one direction it is a ratio machine and in the other it is a proportion machine. 
Puzzle
Hint
Solution 
Adding Car Lane  You
might think that since 1 more lane is a third of the existing
3 lanes, the traffic load is reduced by 1/3.
But you would be wrong.
Let's use T to mark the total traffic load (for example, 3,000 cars per hour.) With 3 lanes the laod at each lane is ^{T}/_{3} or ^{4}/_{12} of T.So each of the 3 original lanes contributes ^{1}/_{4} of its original load to the new lane.(In our example, each lane carries 1,000 cars per hour.)With 4 lanes the laod at each lane is ^{T}/_{4} or ^{3}/_{12} of T. 
Pazzle
Hint Solution 