Hello there! We are talking about 86 being part of a number, so we are looking for the whole. To find the number we are looking for, we can write and solve a proportion. Set it up like this:
86/x = 45/100
86 is 45% of a number. We know the part, so now we are looking for the whole. 45% is part of 100%, so we put that part together. Cross multiply the digits. 100 * 86 is 8,600. 45 * x is 45x. That simplifies to 8,600 = 45x. Now, divide each side by 45 to isolate the x. 45x/45 cancels out. 8,600/45 is 191.1111111 or 191 1/9 in fraction form. There. x = 191 1/9 86 is 45% or 191 1/9
Note: Or, if you have to round to the nearest whole number, the answer is 191, or if you have to round to the nearest tenth, the answer is 191.1. It all depends on if the answer needs to be rounded or exact.