State which is greater: (i) `(8+9)xx10\ and\ 8+9xx10` (ii) `(8-9)xx10\ and\ 8-9xx10` (iii) `{(-2)-5}xx(-6)` and `(-2)-5xx(-6)`

Simplify: i 8xx(-15) + 8xx6 ii (-18)xx7 + (-18)xx(-4) iii 15xx(-32) + 15xx(-18) iv 16xx(-9) + (-8) xx (-9)

Find each of the following products: (-115)xx8 (ii) 9xx(-3)xx(-6) (-12) xx(-13)xx(-5)

1/2xx 5/4 + 6/8 xx 10/9

Write the numeral whose expanded form is given below: ( i ) 6 xx 10^(4)+3 xx 10^(3)+0 xx 10^(2)+7 xx 10^(1)+8 xx 10^(0) ( ii ) 9 xx 10^(6)+7 xx 10^(5)+0 xx 10^(4)+3 xx 10^(3)+2 xx 10^(2)+9 xx 10^(1)+6 xx 10^(0) ( iii ) 8 xx 10^(5)+6 xx 10^(4)+4 xx 10^(3)+2 xx 10^(2)+9 xx 10^(1)+6 xx 10^(0)

Fill in the blanks i (-6)xx(........) = 6 ii (-18)xx(.......) = (-18) iii (-8) xx (-9) = (-9) xx (...) iv 7 xx (-3) = (-3) xx (…) v {(-5)x3}x(-6) = (...)xx{3xx(-6)} vi (-5)x(...)=0

Find the product: (i) (9)/(2)xx((-7)/(4)) (ii) (3)/(10)xx(-9)( iii) (-6)/(5)xx(9)/(11) (iv) (3)/(7)xx((-2)/(5))( v) (3)/(-5)xx(-5)/(3)

State True or False : 8xx10^(6)+2xx10^(4)+5xx10^(2)+9xx10^(@)=8020509

Evaluate without multiplying directly : (i) 33xx27 " " (ii) 103xx97 " " (iii) 9.8xx10.2 .