At McDonalds, a packet of ranch dressing has 10 more calories than eight side salads. Three side salads and two packets of ranch dressing have a total of 400 calories. How many calories are in each item?
R = 8S +10 3S + 2R = 400 Substitute first formula into second formula 3S + 2(8S +10) = 400 3S + 16S + 20 = 400 19S +20 =400 19S + 20 -20 = 400 – 20 19S = 380 19S / 19 = 380/19 S = 20 Plug 20 into first formula R = 8(20) +10 R = 160+10 R= 170 Side Salads are 20 calories and Ranch Dressing is 170 calories.
