In a village the number of houses and the number of flats are in the ratio 7 : 4. The number of flats and the number of bungalows are in the ratio 8 : 5 . There are 50 bungalows in the village. How many houses are there in the village?

H:F F:B7:4 8:550 bungalows, so bungalows have been multiplied by 10 to get from 5 to 50. So now we have to do the same process to the flats so we multiply 8 by 10 to get 80 flats. Now we need to get to 80 flats in the house to flat ratio. So to get from 4 to 80 we need to multiply by 20. This gives us the same number of flats on both ratios. We also need to multiply the houses by 20, so it is 7 x 20 = 140. So the number of houses in the village is 140.