Please see the attachment. I am sorry to say that the answer by u is not correct . the answer is 390 sq metre. Please look at the steps carefully.
you are right dear...i already told that
listen it is correct but incomplete after that we have to subtract 630 from 390
dear,then u are actually finding the area that is Not to be covered with grass.!!!
yup we have to find that only becoz they have told laid with grass