1. B
2. D
3. A
You're welcome to all
4/9, 12/25
3/7, 18/42
5/11, 20/45
5/8, 15/25
Which ratios form a proportion with 18/30?
20/35
50/90
36/48
60/100
Which proportion has cross products of 5 x 24 and 8 x 15?
5/8 x 15/24
5/24 x 8/15
8/24 x 15/5
15/8 x 5/24
2. D
3. A
You're welcome to all
1) 4/9 and 12/25:
Cross products: 4 x 25 = 100 and 9 x 12 = 108
Since the cross products are not equal (100 ≠108), these ratios do not form a proportion.
2) 3/7 and 18/42:
Cross products: 3 x 42 = 126 and 7 x 18 = 126
In this case, the cross products are equal (126 = 126), which means these ratios form a proportion.
3) 5/11 and 20/45:
Cross products: 5 x 45 = 225 and 11 x 20 = 220
Since the cross products are not equal (225 ≠220), these ratios do not form a proportion.
4) 5/8 and 15/25:
Cross products: 5 x 25 = 125 and 8 x 15 = 120
Again, the cross products are not equal (125 ≠120), so these ratios do not form a proportion.
From the given options, only the ratios 3/7 and 18/42 form a proportion.
Now let's move on to the next question:
To determine if a ratio forms a proportion with 18/30, we need to find ratios whose cross products are equal to 18 x 30 = 540.
1) 20/35:
Cross product: 20 x 30 = 600
Since the cross product is not equal to 540 (600 ≠540), this ratio does not form a proportion with 18/30.
2) 50/90:
Cross product: 50 x 30 = 1500
Again, the cross product is not equal to 540 (1500 ≠540), so this ratio does not form a proportion with 18/30.
3) 36/48:
Cross product: 36 x 30 = 1080
Once again, the cross product is not equal to 540 (1080 ≠540), so this ratio does not form a proportion with 18/30.
4) 60/100:
Cross product: 60 x 30 = 1800
Since the cross product is not equal to 540 (1800 ≠540), this ratio does not form a proportion with 18/30.
From the given options, none of the ratios form a proportion with 18/30.
Finally, let's determine which proportion has cross products of 5 x 24 and 8 x 15.
1) 5/8 x 15/24:
Cross product: 5 x 24 = 120 and 8 x 15 = 120
In this case, the cross products are equal (120 = 120), which means this proportion has the desired cross products.
2) 5/24 x 8/15:
Cross product: 5 x 15 = 75 and 24 x 8 = 192
Since the cross products are not equal (75 ≠192), this proportion does not have the desired cross products.
3) 8/24 x 15/5:
Cross product: 8 x 5 = 40 and 24 x 15 = 360
Once again, the cross products are not equal (40 ≠360), so this proportion does not have the desired cross products.
4) 15/8 x 5/24:
Cross product: 15 x 24 = 360 and 8 x 5 = 40
The cross products are not equal (360 ≠40), so this proportion does not have the desired cross products.
Therefore, the proportion 5/8 x 15/24 is the one with cross products of 5 x 24 and 8 x 15.