15% x
100 1.15 X is your variable, your unknown number and 15% has to always be over 100 , Then you have to cross multiply and divide 100 because that is the only number basically you have to just multiply across and divide 100 to make it to the nearest cent you have to round the last two numbers after the decimal Representing money.. Hope this helps!!
The books are $5, and the magazines are $10. I’m not sure which way you want it explained but since magazines are twice the price of books, you can solve the equation 3b + 2b = 25. This gives you b=5 which you just multiply by 2 giving you the price of a magazine.
The formula for finding the area of a trapezoid is: sum of bases*height*1/2
By plugging in the information that we already have, we know: (119+65)*height*1/2=5658
184*1/2*height=5658
92*height=5658
height=61.5cm.
Check:
119+65=184
184*61.5=11316
11316*1/2=5658