arithmetic

ARITHMETIC

Integers: Integers numbers, I = {...., -4, -3, -2, -1, 0, 1, 2, 3, 4, .....}. Some integers are positive, some are negative and the integer 0 is neither positive nor negative.

Even Integers: Even Integers are {...., -6, -4, -2, 0, 2, 4, 6, 8, ...}. Integers that are multiples of 2 are called Even Integers.

Odd Integers: Odd Integers are {...., -7, -5, -3, -1, 1, 3, 5, 7, ....}.

Consecutive Integers: 30, 31, 32, 33, 34 or -4, -5, -6, -7, -8 are called Consecutive Integers.

Prime Number: Prime Numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, ....

Fractions: A Fraction is a number of the form a/b, where a and b are integers and b not equal to 0. Here, the ais called the numerator of the fraction and b is called the denominator.

Mixed Fraction: An expression such as 4 5/6 is called a mixed fraction. It means 4+5/6.

Decimals: In our number system, all numbers can be expressed in decimal form using base 10. A decimal point is used and the place value for each digit corresponds to a power of 10, depending on its position relative to the decimal point. For example, the number 78.564 has 5 digits, where

"7" is the "tens" digit; the place value for "7" is 10

"8" is the "units" digit; the place value for "8" is 1.

"5" is the "tenths" digit; the place value for "5" is 1/10.

"6" is the "hundredths" digit; the place value for "6" is 1/100.

"4" is the "thousandths" digit; the place value for "4" is 1/1000.

Therefore, 78.564 is a short way of writing 

(7)(10)+(8)(1)+(5)(1/10)+(6)(1/100)+(4)(1/1000), or

70+8+0.5+0.06+0.004=78.564

Percent: The term percent means per hundred or divided by one hundred. Therefore,

56% = 56/100 = 0.56;  500% = 500/100 = 5 ; 0.6% = 0.6/100 = 0.006

To find out what 40% of 560 is, you multiply 560 by either 0.40 or 40/100

40% of 560 = (560)(0.40) = 224

To find out what percent of 50 is 5, you set up the following equation and solve for x:

5/50 = x/100

x = 500/50 

x = 10

So 5 is 10% of 50.

Ratio: The ratio of the number 6 to the number 30 can be expressed in several ways; 

for example,

6 to 30

6:30 or 6/30 or ration can be 3/10.

Absolute Value: The absolute value of a number N, denoted by |N|, is defined to be N if N is positive or zero and -N if N is negative. For example,

|1/2| = 1/2, |0| = 0, and |-2.6| = -(-2.6) = 2.6.