There are 175 marbles in a basket. 0.2 of them are gold marbles, and the rest are silver and black marbles. If there are 37 as many silver marbles as black marbles. How many black marbles are there?
| Gold marbles |
Silver marbles |
Black marbles |
Total |
| 1 u |
4 u |
5 u |
| |
3 p |
7 p |
|
0.2 =
210 =
15 Fraction of marbles that are silver and black marbles
= 1 -
15 =
45 Total number of marbles = 5 u
5 u = 175
1 u = 175 ÷ 5 = 35
Number of silver marbles and black marbles
= 4 u
= 4 x 35
= 140
Number of silver and black marbles
= 3 p + 7 p
= 10 p
10 p = 140
1 p = 140 ÷ 10 = 14
Number of black marbles
= 7 p
= 7 x 14
= 98
Answer(s): 98
