648 is 54% of ?
find the unknown value.

The answer to this problem is 349.92. assuming that 648 is 100 we can rewrite the problem like so: 648=100. now we have 2 equations 648=100% x=54% since the left and right sides have the same unit we can do something like so: 648/x=100%/54% now solve 648/x=100/54
(648/x)*x=(100/54)*x       - we multiply both sides of the equation by x
648=1.8518518518519*x       - we divide both sides of the equation by (1.8518518518519) to get x
648/1.8518518518519=x 
349.92=x 
x=349.92

Answer: d. 39 cmin the diagram, the approximate length of the minor arc de is 39 centimetres.step-by-step explanation: the formula for the length of an arc in a circle is as displayed below.let the length of the minor arc de = xx = 2( pi )r × angle of sector / 360°from this, we will substitute the values given from the problem into the formula to obtain the length of the minor arc de.x = 2( pi )r × angle of sector / 360°r = radius = 25cmpi as an approximate value = 3.14angle of sector = 120°x = 2( 3.14 )( 25 ) × 120° / 360°x = 157 × 1 / 4x = 39.25x = 39 ( rounded to the nearest whole number as an approximate value )