Michael was an avid stamp collector. The ratio of the number of local stamps to the number of foreign stamps he had was 4: 7.After receiving 87 more foreign stamps from his mother, the ratio became 2: 5.How many more foreign stamps did he have than local stamps in the end?
The ratio 2:5 is the same as 4:10
So 87 is 3 parts in this ratio since 10-7 is 3.
One part would be 29.
Since there are 3 more parts of foreign stamps than local, 29*3=87 more foreign.