Comparing two rational numbers
Use fraction form:
Make the
denominators the same and compare the numerators. The number with the smaller
numerator is smaller. For example, to compare
a/b and c/d, we rewrite
a/b=a*d/b*d
= ad/bd and
c/d = c*b/d*b=bc/bd
Now just compare the numerators : "ad" and
"bc"
Multiplying and Dividing Rational Numbers
Multiplying
and dividing rational numbers in decimal form is the same as multiplying and
dividing integers. The decimal place of the product is the same of all decimals
of all multiplied numbers. For example,
3.12*2.4.
Solution => 3.12*2.4=7.488
When
multiplying or dividing rational numbers in fractional form, you multiply the
numerators (N*N) and then multiply the denominators (D*D).
When
dividing rational numbers in fractional form, first take the reciprocal of the
divisor, and then multiply the numerators and the denominators.
Example => 5/9 divided by 2/7 .
Solution => 5/9 * 7/2 = 35/18
Adding Rational numbers
Adding
and Subtracting rational numbers in decimal form is the same as adding and
subtracting integers.
Example => -3.54+2.79=-0.75
When
adding or subtracting rational numbers in fractional form, first make the
denominator equal, and then add or subtract the numerators.
