thet 3 identical resistors R1,R2 and R3 are connected to a battery as shown in the fig. what wil b d ratio of voltages across R1 andR2?

Here R2 and R3 are in parallel so the voltage across them is same. Suppose the voltage across R1 is V1 and voltage across R2 is V2.

And also the current flowing in R1 and in the parallel combination other two is same.Let it be I

then V1=IR1

V2=I(R2R3/R2+R3)

Now V1/V2=R1(R2+R3)/R2R3