You have to translate the statement into a mathematical expression...
Six times the number of cattle, if we let c be the number of cattle is:
6c
Less 87 means to subtract 87 so
6c-87
is 999 means
=999
so all together we have:
6c-87=999 now we need to isolate the variable by itself on one side of the equal sign....
6c-87=999 add 87 to both sides
6c=1086 divide both sides by 6
c=181
So there are 181 cattle.
