5 math questions, 10 POINTS♥♥

5. 16 is what percent of 34?
a)16 = n · 34; 47.1%
b)34 = 16 · n; 40%
c)34 = 16 · n; 2.1%
d)16 = n · 34; 51.8%

6. 68 is 78% of what number? (1 point)
a)x = 68 · 0.78; 53
b)68 = 0.78 · x; 87.2
c)0.78 = 68 · x; 59.3
d)68 = 0.78 · x; 90.7

7. Find the percent of change in altitude if a weather balloon moves from 100 ft to 103 ft. Describe the percent of change as an increase or decrease. Round to the nearest tenth if necessary. (1 point)
a)1.6%; increase
b)3.4%; decrease
c)3%; increase
d)3%; decrease

8. The circulation of a newsletter decreased from 5,200 to 3,140. Find the percent of decrease in circulation to the nearest percent. (1 point)
a)66%
b)40%
c)166%
d)6%

10. A cell phone company orders 500 new phones from a manufacturer. If the probability of a phone being defective is 2.6%, predict how many of the phones are likely to be defective. Round to the nearest whole number. (1 point)
a)16 phones
b)13 phones
c)11 phones
d)130 phones

5) a - (16/34) * 100 = 47.1
6) b - 68 / 0.78 = 87.2
7) c - ((103-100) / 100) * 100 = 3
8) b - ((5200 - 3140 / 5200) * 100 =39,6 ~ 40
10) b - (2.6 / 100) * 500 = 0.026 * 500 = 13

~ means approximately

The reason James Kim got a different answer from Darko for #8
is that James Kim has worked out the difference as a percentage of the final value
whereas it should be a percentage of the initial value,
so I agree with Darko (Hence TU)

5 a 6 b 7 c 8 a 10 b