6th grade math
posted by Alex on .
Hi.. i'm a little confused on using proprtion equations to solve percent problem. can you check the following? Is there a different way to solve?
equation: is(part)/of(whatnumber)= %/100
1. What is 94% of 43?
x/43 = 94/100
100x = 43*94 (cross multiply)
100x = 4042
x = 4042/100
x = 40.42
2. 63 is what percent of 84?
63/84 = x/100
84x = 63*100
84x = 6300
x = 6300/84
x = 75%
3. 5% of what is 3.4?
3.4/x = 5/100
5x = 100*3.4
5x = 340
x = 340/8
x = 68
4. What is 5% of 28?
x/28 = 5/100
100x = 28*5
100x = 140
x = 140/100
x = 1.4
5. 15% of what is 6.3?
6.3/x = 15/100
15x = 100*6.3
15x = 630
x = 630/15
x = 42
6. 3.8 is what percent of 76?
3.8/76 = x/100
76x = 100*3.8
76x = 380
x = 380/76
x = 5
7. Find 64% of 48.
x/48 = 64/100
100x = 64*48
100x = 3072
x = 3072/100
x = 30.72
8. What percent of 90 is 6?
6/90 = x/100
90x = 6*100
90x = 600
x = 600/9
x = 66.67% ?
9. 105 is 5% of what number?
105/x = 5/100
5x = 105*100
5x = 10500
x = 10500/5
x = 2100 ?
10. What percent of 69 is 138?
138/69 = x/100
69x = 138*100
69x = 13800
x = 13800/69
x = 200
Thanks

Change percent to decimal and multiply.
1. .94 * 43 = 40.42
8. 6/90 = .066667 (convert to percentage by multiplying by 100)
9. 105/.05 = 2100
Your answers seem right, but you can check again by using decimals.