Final answer:
Multiplying a number by 1.98 means you've increased it by 98%. This is calculated by subtracting 1 from 1.98 to find the proportional increase, and then converting that to a percentage by multiplying by 100.
Step-by-step explanation:
To find what percentage increase is represented by multiplying a number by 1.98, we need to compare this multiplication factor to the original value, which is 1 (or 100%). Multiplying by 1.98 means that we have the original amount, plus an additional 0.98 of that amount. To find out what percent increase this represents, we subtract 1 from 1.98 to find the increase over the original amount, which gives us 0.98, and then we convert that decimal to a percentage.
We do this by multiplying the decimal by 100. Thus, 0.98 multiplied by 100 gives us 98%. This means that multiplying by 1.98 is the same as increasing by 98%.
As an example, just like when we multiply 45.86 by 100 we move the decimal point 2 places to the right (resulting in 4586), when we want to find the percentage increase, we can simply multiply the decimal increase by 100.