what is the answer to this maths problem?

I may be wrong, but I assume that this problem is equivalent to:

1/((1/4.8)+(1/3.2)) Parentheses always help clarify things.

If this is the case first compute the denominator as follows:
First get rid of the decimal points by multiplying numerators and denominators by 10.
(1/4.8) = 10/48
(1/3.2) = 10/32

96 is the Least Common Denominator - LCD - of 48 and 32

Hence 10/48 = (10x2)/(48x2) = 20/96
and (10/32) = (10x3)/(32x3) = 30/96

(20/96) + (30/96) = 50/96 and

1/(50/96) = (1x96)/((50x96)/96) = 96/50.

Reducing by dividing 96 and 50 by 2 gets the final answer of 48/25.<<<<<<<

If the teacher insists on an answer in decimal form, get out your calculator and divide 48 by 25 getting 1.92 <<<<<<<
(or do it by long division for the same result.)

I hope that this helps!

1/(1/4.8 + 1/3.2)
= 1/(20/96 + 30/96)
= 1/(50/96)
= 1(96/50)
= 96/50
= 48/25 (1.92)

what is the "problem"? fill in the gaps? and what ia .4.83.2 at the last line?

change the denominator to whole numbers ..

1 / (10/48 + 10/32)
= 1/ ( (320+480)/1536 )
=1/ (800/1536)
= 1 x 48/25
=1.92

9.6