whole numbers

the set of counting numbers and zero (0, 1, 2, 3, 4, .....)

thousandth

one of 1,000 equal parts; the third place to the right of the decimal point

tenth

one of 10 equal parts; the first place to the right of the decimal point

round

to approximate a number to a given place value

reasonable

logical or sensible

place value

the value determined by the position of a digit in a number

mixed number

a number composed of a whole number and a fraction

improper fraction

a fraction in which the numerator is greater than or equal to the denominator

hundredth

one of 100 equal parts; the second place to the right of the decimal point

front-end estimation

an estimation made using the front-end of a digit number

fraction

a number that names a part of a whole or part of a group

estimate

an answer that is close to the exact answer; to guess about

digit

one of the symbols 0,1,2,3,4,5,6,7,8, and 9 used to write numbers

decimal point

the dot used to separate the ones place from the tenths place in a decimal number

decimal number

a number that uses a decimal point to show tenths, hundredths, and thousandths

compensation

an estimation strategy in which numbers are rounded and then mentally adjusted

compatible numbers

pairs of numbers that can be easily computed mentally

approximate

to estimate; to come close to; almost exact or correct