add addition Arabic numeral arithmetic progression bi- billion calculate calculation cardinal cardinal number coefficient common denominator constant cube cube root D decimal(n) decimal(a) decimal point demi- denominator digit divide dividend divisible division divisor double-digit double figures eight eighteen eighth eighty eleven equal(a) equal(v) equals sign even exponent factor(n) factor(v) factorial fifteen fifth fifty fig. figure five forty four fourteen fourth fraction geometric progression gross HCF hundred improper fraction indivisible infinity integer L logarithm lowest common denominator M median(n) median(a) million multiple multiplication multiplication sign multiplication table -nd negative nine nineteen ninety ninth No. nos. nought number numeral numerator numerical O oblique one ordinal number pi plot point positive prime number product proper fraction proportion quadr- quadrillion quadruple quotient -rd roman numeral root round score second serial number set single figures six sixteen sixty square(n) square(v) squared square root -st subtract sum take ten tenth tertiary tetra- thirteen thirty thousand three three-quarter threescore tri- trillion twelve twenty twice unit V vulgar fraction whole number X zero