Hello, I'm from Indonesia. I hope that answer your question.
This is a standard relationship/systems of equations question. Here is how you attack it. Firstly, set up equations to represent the relationships. Ed = 4*Kim That shows that Ed has four times as many pins as Kim. Next, we see that the two have 25 together. So: Ed + Kim = 25 Now we have our two equations. In order to solve, we need to get one of the equations down to one variable. We can achieve this via substitution. The first equation tells us that we can substitute 4*Kim for Ed (in the second equation). So, let's do just that: 4*Kim + Kim = 255*Kim = 25Kim = 5 Using the first equation again, we can solve for Ed: Ed = 4*KimEd = 4*(5)<span>Ed = 20</span>
To find the number of red bricks used, you can create a part to part to whole ratio from the simple ratio of red to grey brick they give.
Then, use the total to create an equivalent ratio with the actual total number of bricks (140).
<u>5 red </u> <u>100 red</u>
<u>2 grey</u> = <u>40 grey</u>
7 total 140 total
<u>
</u>Each time, the simple ratio was multiplied by 20 to get the actual totals for each color.
<u>
</u>There were 100 red bricks used.<u>
</u>
Place value chart can be extended to include numbers less than one,which are sometimes called decimal fractions